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INTERNET-DRAFT R. deBry
draft-ietf-ipp-model-04.txt IBM Corporation
T. Hastings
Xerox Corporation
R. Herriot
Sun Microsystems
S. Isaacson
Novell, Inc.
P. Powell
San Diego State University
July 25, 1997
Internet Printing Protocol/1.0: Model and Semantics
Status of this Memo
This document is an Internet-Draft. Internet-Drafts are working
documents of the Internet Engineering Task Force (IETF), its areas,
and its working groups. Note that other groups may also distribute
working documents as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress".
To learn the current status of any Internet-Draft, please check the
"1id-abstracts.txt" listing contained in the Internet-Drafts Shadow
Directories on ftp.is.co.za (Africa), nic.nordu.net (Europe),
munnari.oz.au (Pacific Rim), ds.internic.net (US East Coast), or
ftp.isi.edu (US West Coast).
Abstract
This document is one of a set of documents, which together describe
all aspects of a new Internet Printing Protocol (IPP). IPP is an
application level protocol that can be used for distributed printing
using Internet tools and technology. The protocol is heavily
influenced by the printing model introduced in the Document Printing
Application (ISO/IEC 10175 DPA) standard. Although DPA specifies both
end user and administrative features, IPP version 1.0 is focused only
on end user functionality.
The full set of IPP documents includes:
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Internet Printing Protocol: Requirements
Internet Printing Protocol/1.0: Model and Semantics
Internet Printing Protocol/1.0: Security
Internet Printing Protocol/1.0: Protocol Specification
Internet Printing Protocol/1.0: Directory Schema
The requirements document takes a broad look at distributed printing
functionality, and it enumerates real-life scenarios that help to
clarify the features that need to be included in a printing protocol
for the Internet. It identifies requirements for three types of
users: end users, operators, and administrators. The requirements
document calls out a subset of end user requirements that MUST be
satisfied in the first version of IPP. Operator and administrator
requirements are out of scope for v1.0. The model and semantics
document describes a simplified model with abstract objects, their
attributes, and their operations. The model introduces a Printer
object and a Job object. The Job object supports multiple documents
per job. The security document covers potential threats and proposed
counters to those threats. The protocol specification is formal
document which incorporates the ideas in all the other documents into
a concrete mapping using clearly defined data representations and
transport protocol mappings that real implementers can use to develop
interoperable client and server side components. Finally, the
directory schema document shows a generic schema for directory service
entries that represent instances of IPP Printers.
This document is the "Internet Printing Protocol/1.0: Model and
Semantics" document.
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Table of Contents
1. Simplified Printing Model......................................7
2. IPP Objects....................................................9
2.1 Printer Object .............................................10
2.2 Job Object .................................................12
2.3 Document Object ............................................12
2.4 Object Relationships .......................................12
2.5 Object Identity ............................................13
3. IPP Operations................................................13
3.1 General Semantics ..........................................14
3.1.1 Operation Status Codes and Messages......................14
3.1.2 Security and Query Operations............................14
3.1.3 Job Creation Operations..................................15
3.2 Printer Operations .........................................16
3.2.1 Get-Operations Operation.................................16
3.2.1.1 Get-Operations Request ................................16
3.2.1.2 Get-Operations Response ...............................16
3.2.2 Print-Job Operation......................................17
3.2.2.1 Print-Job Request .....................................17
3.2.2.2 Print-Job Response ....................................20
3.2.3 Print-URI Operation......................................20
3.2.4 Validate-Job Operation...................................21
3.2.5 Create-Job Operation.....................................21
3.2.6 Get-Attributes Operation.................................21
3.2.6.1 Get-Attributes Request ................................22
3.2.6.2 Get-Attributes Response ...............................23
3.2.7 Get-Jobs Operation.......................................23
3.2.7.1 Get-Jobs Request ......................................24
3.2.7.2 Get-Jobs Response .....................................24
3.3 Job Operations .............................................25
3.3.1 Send-Document Operation..................................25
3.3.1.1 Send-Document Request .................................25
3.3.1.2 Send-Document Response ................................25
3.3.2 Send-URI Operation.......................................25
3.3.3 Cancel Job Operation.....................................26
3.3.3.1 Cancel-Job Request ....................................26
3.3.3.2 Cancel-Job Response ...................................26
3.3.4 Get-Attributes Operation.................................26
3.3.4.1 Get-Attributes Request ................................26
4. Object Attributes.............................................27
4.1 Attribute Syntaxes .........................................27
4.1.1 Attribute Extensibility..................................29
4.2 Job Template Attributes ....................................31
4.2.1 job-sheets (type4 keyword)...............................34
4.2.2 notify-events (1setOf type2 keyword).....................35
4.2.3 notify-addresses (1setOf uri)............................35
4.2.4 job-priority (integer(1:100))............................36
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4.2.5 job-hold-until (type4 keyword)...........................36
4.2.6 multiple-document-handling (type2 keyword)...............37
4.2.7 media (type4 keyword)....................................37
4.2.8 number-up (type3 keyword)................................38
4.2.9 sides (type2 keyword)....................................38
4.2.10 printer-resolution (resoultion)..........................39
4.2.11 print-quality (type2 enum)...............................39
4.2.12 finishings (1setOf type2 enum)...........................39
4.2.13 copies (integer(1:2**31 - 1))............................40
4.2.14 document-format (type2 enum).............................40
4.2.15 compression (type3 keyword)..............................41
4.2.16 job-k-octets (integer(0:2**31 - 1))......................41
4.2.17 job-impressions (integer(0:2**31 - 1))...................41
4.2.18 job-media-sheets (integer(0:2**31 - 1))..................41
4.3 Job Description Attributes .................................42
4.3.1 job-uri (uri)............................................43
4.3.2 job-uri-user (uri).......................................44
4.3.3 job-name (name)..........................................44
4.3.4 job-originating-user (name)..............................44
4.3.5 job-originating-host (name)..............................44
4.3.6 user-human-language (human-language).....................44
4.3.7 user-content-char-set (char-set).........................45
4.3.8 job-state (type1 enum)...................................45
4.3.9 job-state-reasons (1setOf type2 keyword)................47
4.3.10 job-state-message (text).................................49
4.3.11 output-device-assigned (name)............................49
4.3.12 time-since-pending (integer).............................49
4.3.13 time-since-processing (integer)..........................49
4.3.14 time-since-completed (integer)...........................49
4.3.15 number-of-intervening-jobs (integer(0:2**31 - 1))........49
4.3.16 job-message-from-operator (text).........................50
4.3.17 job-k-octets-processed (integer(0:2**31 - 1))............50
4.3.18 job-impressions-completed (integer(0:2**31 - 1))........50
4.3.19 job-media-sheets-completed (integer(0:2**31 - 1))........50
4.4 Document Attributes ........................................50
4.4.1 document-name (name).....................................51
4.4.2 document-format (type2 enum).............................51
4.4.3 document-uri (uri).......................................51
4.5 Printer Description Attributes .............................51
4.5.1 printer-uri (uri)........................................53
4.5.2 printer-uri-user (uri)...................................53
4.5.3 printer-name (name)......................................53
4.5.4 printer-location (text)..................................53
4.5.5 printer-description (text)...............................53
4.5.6 printer-more-info-site (uri).............................53
4.5.7 printer-driver-installer (uri)...........................54
4.5.8 printer-make-and-model (text)............................54
4.5.9 printer-more-info-manufacturer (uri).....................54
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4.5.10 printer-state (type1 enum)...............................54
4.5.11 printer-state-reasons (1setOf type2 keyword).............55
4.5.12 printer-state-message (text).............................57
4.5.13 printer-is-accepting-jobs (boolean)......................57
4.5.14 queued-job-count (integer(0:2**31 - 1))..................58
4.5.15 printer-message-from-operator (text).....................58
4.5.16 printer-human-language (human-language)..................58
4.5.17 printer-human-language-supported (1setOf human-language).58
4.5.18 printer-content-char-set (char-set)......................58
4.5.19 printer-content-char-set-supported (1setOf char-set).....58
4.5.20 color-supported (boolean)................................58
4.5.21 pdl-override (type2 keyword).............................58
4.5.22 Security Related Attributes..............................59
4.5.22.1 message-protection-supported (keyword) ................60
4.5.22.2 authentication-authorization-supported (keyword) ......60
4.5.23 best-effort (1setOf boolean).............................60
5. Conformance...................................................61
5.1 Conditionally Mandatory ....................................61
5.2 Client Conformance Requirements ............................62
5.3 Printer Object Conformance Requirements ....................62
5.3.1 Objects..................................................62
5.3.2 Operations...............................................63
5.3.3 Attributes...............................................63
5.3.4 Printer extensions.......................................64
5.3.5 Attribute Syntaxes.......................................64
5.4 Security Conformance Requirements ..........................64
6. IANA Considerations (registered and private extensions).......65
6.1 Typed Extensions ...........................................65
6.1.1 Type1....................................................65
6.1.2 Type2....................................................65
6.1.3 Type3....................................................66
6.1.4 Type4....................................................66
6.2 Registration of MIME types/sub-types for document-formats ..66
7. Security Considerations.......................................66
8. References....................................................67
9. Author's Address..............................................68
10. APPENDIX A: Terminology.......................................71
10.1 Conformance Terminology ....................................71
10.1.1 MUST.....................................................71
10.1.2 MUST NOT.................................................71
10.1.3 SHOULD...................................................71
10.1.4 SHOULD NOT...............................................71
10.1.5 MAY......................................................71
10.1.6 CONDITIONALLY MANDATORY..................................72
10.1.7 NEED NOT.................................................73
10.2 Model Terminology ..........................................74
10.2.1 Keyword..................................................74
10.2.2 Parameters...............................................74
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10.2.2.1 Parameter Name ........................................74
10.2.2.2 Parameter Value .......................................74
10.2.2.3 Parameter Syntax ......................................74
10.2.3 Attributes...............................................75
10.2.3.1 Attribute Name ........................................75
10.2.3.2 Attribute Group Name ..................................75
10.2.3.3 Attribute Value .......................................75
10.2.3.4 Attribute Syntax ......................................76
10.2.4 Supports.................................................76
11. APPENDIX B: Status Codes.....................................77
11.1 Status Codes (type2 keyword) ...............................78
11.1.1 Informational............................................78
11.1.2 Successful Status Codes..................................78
11.1.2.1 successful-ok .........................................78
11.1.2.2 successful-ok-ignored-or-substituted-attributes .......78
11.1.3 Redirection Status Codes.................................78
11.1.4 Client Error Status Codes................................79
11.1.4.1 client-error-bad-request ..............................79
11.1.4.2 client-error-forbidden ................................79
11.1.4.3 client-error-not-authenticated ........................79
11.1.4.4 client-error-not-authorized ...........................79
11.1.4.5 client-error-not-possible .............................80
11.1.4.6 client-error-timeout ..................................80
11.1.4.7 client-error-not-found ................................80
11.1.4.8 client-error-gone .....................................80
11.1.4.9 client-error-request-entity-too-large .................81
11.1.4.10 client-error-request-URI-too-long .....................81
11.1.4.11 client-error-unsupported-document-format ..............81
11.1.4.12 client-error-attribute-not-supported ..................81
11.1.5 Server Error Status Codes................................82
11.1.5.1 server-error-internal- error ..........................82
11.1.5.2 server-error-operation-not-supported ..................82
11.1.5.3 server-error-service-unavailable ......................82
11.1.5.4 server-error-version-not-supported ....................82
11.1.5.5 server-error-device-error .............................83
11.1.5.6 server-error-temporary-error ..........................83
11.2 Status Keywords for IPP Operations .........................84
12. APPENDIX C: "document-format" enum values.....................84
13. APPENDIX D: "media" keyword values...........................88
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1. Simplified Printing Model
In order to a achieve its goal of realizing a workable printing
protocol for the Internet, the Internet Printing Protocol (IPP) is
based on a simplified printing model which abstracts the many
components of real world printing solutions. The Internet is a
distributed computing environment where requesters of print services
(clients, applications, PC drivers, etc.) cooperate and interact with
print service providers. This model and semantics document describes
a simple, abstract model for IPP even though the underlying
configurations may be complex "n-tier" client/server systems. An
important simplifying step in the IPP model is to expose only the key
objects and interfaces required for printing. The model does not
include features, interfaces, and relationships that are beyond the
scope of IPP [20].
The IPP model encapsulates the important components of distributed
printing into three object types:
- Printer (Section 0)
- Job (Section 2.2)
- Document (Section 2.3)
Each object type has an associated set of operations (see section 3)
and attributes (see section 4). The remainder of this document uses
specific model terminology (such as "attributes", "supports",
"keywords", and "parameters") and conformance terminology (such as
"MANDATORY", "MUST", and "OPTIONAL"). Appendix A defines these terms
as they relate to this document.
It is important, however, to understand that in real system
implementations (which lie underneath the abstracted IPP model), there
are other components of a print service which are not explicitly
defined in the IPP model. The following figure illustrates where IPP
fits with respect to these other components.
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+--------------+
| Application |
o +. . . . . . . |
\|/ | Spooler |
/ \ +. . . . . . . | +---------+
End-User | Print Driver |---| File |
+-----------+ +-----+ +------+-------+ +----+----+
| Browser | | GUI | | |
+-----+-----+ +--+--+ | |
| | | |
| +---+------------+---+ |
N D S | | IPP Client |------------+
O I E | +---------+----------+
T R C | |
I E U |
F C R -------------- Transport ------------------
I T I
C O T | --+
A R Y +--------+--------+ |
T Y | IPP Server | |
I +--------+--------+ |
O | |
N +-----------------+ | IPP Printer
| Print Service | |
+-----------------+ |
| --+
+-----------------+
| Output Device(s)|
+-----------------+
An IPP Printer encapsulates the functions normally associated with
physical output devices along with the spooling, scheduling and
multiple device management functions often associated with a print
server. IPP Printers are optionally registered as entries in a
directory where end users find and select them based on some sort of
filtered and context based searching mechanism. The directory is used
to store relatively static information about the Printer, allowing end
users to search for and find Printers that match their search criteria
(name, context, printer capabilities, etc.). The more dynamic
information associated with a Printer includes state, currently loaded
and ready media, number of jobs at the Printer, errors, warnings, and
so forth.
IPP clients implement the IPP protocol on the client side, and give
end users (or programs) the ability to query an IPP Printer and submit
and manage their print jobs. An IPP server is just that part of the
IPP Printer that implements the server-side protocol. The rest of the
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IPP Printer implements the application semantics of the print service
itself. The IPP Printer may be embedded in an output device or may be
implemented on a host on the network that communicates with the output
device.
When a job is submitted to the Printer, the Printer creates a Job
object. The end user then interacts with this new Job to query its
status and monitor the progress of the job. End users may also cancel
the Job. The end user is able to register to receive certain events
that are then routed using the specified notification service(s).
2. IPP Objects
The IPP model introduces objects of type Printer, Job, and Document.
Each object type is defined as a set of possible attributes that may
be supported by each instance of an object of that type. The
attributes (and values) supported by each object instance describe the
implementation (that is the realizable features, functions, and
characteristics either in software or hardware) for that object
instance. For example, the object type "Printer" is defined as set of
attributesthat each instance of a Printer object might potentially
support. In the same manner, the object type "Job" is defined as a
set of attributes that are potentially supported by each instance of a
Job object.
Each attribute included in the set of attributes defining an object
type is labeled as:
- "MANDATORY": each object instance MUST support the attribute.
- "OPTIONAL": each object instance MAY support the attribute.
- "CONDITIONALLY MANDATORY": whether or not the object instance
supports the attribute is determined by a semantic condition.
For example, a Printer object implementation MUST support the
"job-priority-supported" attribute if the implementation knows
about and is able to realize multiple levels of job priorities.
An administrator may set the values to be somewhat more
restrictive that what a given implementation might allow, however
the attribute MUST still be supported.
There is no such similar labeling of attribute values. However, if an
implementation supports an attribute, it must support any non-empty
subset of the possible values for that attribute.
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2.1 Printer Object
A major component of the IPP model is the Printer object. An instance
of a Printer object implements the IPP protocol. Using the protocol,
end users may query the attributes of the Printer, submit Jobs to the
Printer, determine subsequent states of submitted and queued Jobs, and
cancel Jobs (section 3 describes each of the Printer specific
operations in detail). The actual implementation components behind
the Printer abstraction may take on different forms and different
configurations. However, the model abstraction allows the details of
the configuration of real components to remain transparent to the end
user.
The capabilities and state of an IPP Printer are described by its
attributes. Printer attributes are grouped as follows:
"job-template" attributes (section 4.2)
"printer-description" attributes (section 4.5)
Since a Printer object is an abstraction of a generic document output
device and print service provider, an IPP Printer object could be used
to represent any real or virtual device with semantics consistent with
thePrinter object, such as a fax-out device, an imager, or even a CD
writer.
Some examples of configurations supporting a Printer object include:
1) An output device, with no spooling capabilities
2) An output device, with a built-in spooler
3) A print server supporting IPP with one or more associated output
devices
3a) The associated output devices might or might not be capable
of spooling jobs
3b) The associated output devices might or might not support IPP
See the following figures for some examples on how to view IPP Printer
objects implemented on top of various print system configurations.
The embedded case below represents configurations 1 and 2. The hosted
and fan-out figures below represent configuration 3.
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Legend:
##### indicates a Printer object which is
either embedded in an output device or is
hosted in a server. The implementation
might or might not be capable of queuing/spooling.
any indicates any network protocol or direct
connect, including IPP
embedded printer:
output device
+---------------+
O +--------+ | ########### |
/|\ | client |------------IPP------------># Printer # |
/ \ +--------+ | # Object # |
| ########### |
+---------------+
hosted printer:
+---------------+
O +--------+ ########### | |
/|\ | client |--IPP--># Printer #-any->| output device |
/ \ +--------+ # Object # | |
########### +---------------+
+---------------+
fan out: | |
+-->| output device |
any/ | |
O +--------+ ########### / +---------------+
/|\ | client |-IPP-># Printer #--*
/ \ +--------+ # Object # \ +---------------+
########### any\ | |
+-->| output device |
| |
+---------------+
It is assumed that URIs for IPP Printers are available to end users or
programs that wish to interact with the Printer. Although NOT
MANDATORY, it is RECOMMENDED that Printers be registered in a
directory service which end users and programs can interrogate.
"Internet Printing Protocol: Directory Schema"[24] defines the
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attributes to be associated with a Printer entry in a directory
service.
2.2 Job Object
A Job object is used to model a job. A Job can contain one or more
Documents. The information required to create a Job object is sent in
a create request from the end user via an IPP client to an IPP
Printer. Section 3 describes each of the Job specific operations in
detail.
The characteristics and state of an IPP Job are described by its
attributes. Job attributes are grouped as follows:
"job-template" attributes (optionally supplied by the client/end
user, section 4.2)
"job-description" attributes (set by the Printer, section 4.3)
2.3 Document Object
A Document object consists of either printable data or a reference
(URI) to printable data and a set of Document Attributes (see section
4.4). These Document attributes only describe the data to be printed;
they do not include any specialized document processing instructions.
All document processing instructions are included as Job level
attributes (called Job Template attributes), and they apply equally
to all Documents within a Job.
Currently there are no operations defined for Document objects.
2.4 Object Relationships
Instances of objects within the system have relationships that MUST be
maintained persistently along with the persistent storage of the
object attributes. An instance of a Printer object usually represents
one or more output devices. A Printer object may represent a logical
device which "processes" jobs but never actually uses a physical
output device to put marks on paper (for example a Web page publisher
or an interface into an online document archive or repository). A
Printer can contain zero or more Job objects. An instance of a Job
object is contained in exactly one Printer object (the same document
data could be sent to a the same or a different Printer, but the
corresponding Job object would be an identical, but different Job
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object). A Job object contains one or more Documents. If the
Document is simply a reference to some print data stream, the
referenced document may be used in multiple Documents in the same Job
or even in different Jobs, though each Document contains its own copy
of the reference. If the Document is not just a reference, but an
actual stream of print data, the stream is contained in only one
Document, although there can be copies of the same document data in
other Documents in the same or different Jobs.
2.5 Object Identity
All instances of Printer and Job objects have a URI so that they can
persistently and unambiguously referenced. The IPP model requires
that these values be URIs as defined by RFC 1738 [11] and RFC 1808.
In addition to an identifier attribute, instances of Printer and Job
objects may have a name. An object name need not be unique across all
instances of all objects. The Printer name is chosen and set by an
administrator. If not supplied by the client, the Printer creates the
Job name. In all cases, the name only has local meaning, and it is
not constrained to be unique.
To summarize, each instance of Printer and Job objects will have two
identifying attributes:
- "xxx-uri": The unique identifier for this object instance
- "xxx-name": The non unique name for this object instance
Document objects sent to an IPP Printer only have names, no
identifiers. The "document-name" attribute is used to store the name
of the Document. This name is just of interest within the context of
a Job; it need not be unique.
If Documents are printed by reference, the corresponding document
object contains a "document-uri" attribute, but the value of this
attribute is a reference to the document data to be printed; it is not
the unique identifier of the Document object itself.
3. IPP Operations
Jobs and Printers each have a set of associated operations.
Operations consist of requests and responses. When a client
communicates with an IPP object, it issues an operation request to the
URI for that object. Each request carries along with it the input
parameters and any data required to perform the operation. Each
request requires a response from the object indicating success or
failure of the operation including output parameters, status codes,
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and/or status messages. The representation and encoding of IPP
operations, parameters, and attributes is described in "Internet
Printing Protocol: Protocol Specification" [23]. This section of this
document describes the IPP operations in terms of their contents and
semantics including both the request and the response for each
operation.
The Printer operations are fully defined in section ??:
Get-Operations (section 3.2.1)
Print-Job (section 3.2.2)
Print-URI (section 3.2.3)
Validate-Job (section 3.2.4)
Create-Job (section 3.2.5)
Get-Jobs (section 3.3.3)
Get-Attributes (section 3.3.4)
The Job operations are fully defined in section ??:
Send-Document (section 3.3.1)
Send-URI (section 3.3.2)
Cancel-Job (section 3.3.3)
Get-Attributes (section 3.3.4)
There are no Document operations.
3.1 General Semantics
3.1.1 Operation Status Codes and Messages
Every operation response returns a MANDATORY status code and an
OPTIONAL status message. A status code provides information on the
processing of a request. A message provides a short textual
description of the status of the operation. The status code is
intended for use by automata and a status message is intended for the
human user. An IPP application (i.e. a browser, GUI, print driver or
gateway) is not required to examine or display the message. Status
codes and suggested corresponding status messages are described in
section 11.. In most cases, if the status code indicates an error (the
code belongs to either the "client-error" or the "server-error"
group), there are additional output parameters (such as "unsupported-
attributes") returned that are not returned in the successful case.
3.1.2 Security and Query Operations
In many of these IPP operations, a client supplies a list of
attributes to be returned in the response. A Printer may be
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configured, for security reasons, not to return all attributes that a
client requests. It may even return none of the requested attributes.
In such cases, the status returned is the same as if the Printer had
returned all requested attributes. The client cannot tell by such a
response whether the requested attribute was present or absent on the
Printer.
3.1.3 Job Creation Operations
In order to create a new Job object, a client issues a create request.
A create request any one of following three operation requests:
- The Print-Job operation: This operation is used by a client that
wants to create a Job with only a single Document. The operation
allows for the client to "push" the document data to the Printer
by including the document data in the request itself.
- The Print-URI operation: This operation is used by a client that
wants to create a Job with only a single Document, however, the
client wants the Printer to "pull" the document data. In this
case, the client includes only a URI reference to the document
data (not the document data itself).
- The Create-Job operation: This operation is used by a client
that wants to create a Job with multiple Documents. This
operation is followed by an arbitrary number of Send-Document or
Send-URI operations (each creating another Document for this
Job). The Send-Document operation includes the document data
with the operation request (client "pushes" the document data to
the printer), and the Send-URI operation includes only a URI
reference to the document data (the Printer "pulls" the document
data from the referenced location). The last Send-Document or
Send-URI request includes a parameter indicating that this is the
last Document for this Job.
A Create-Job operation followed by only one Send-Document operation is
semantically equivalent to a Print-Job operation, however, for
performance reasons, the client SHOULD use the Print-Job operation for
all single Document Jobs. Throughout this model specification, the
term "create request" is used to refer to any of these three operation
requests.
Also, as the Printer evaluates input parameters and Job Template
attributes in a create request at the time the Job is first submitted,
it makes a decision whether or not to accept or reject the request and
create the Job object. At job submission time, the Printer does not
need to validate the document data or the URI reference to document
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data (in the case of a Print-URI). However, at job processing time,
the Printer might realize any of the following:
- there an error in the document data and it can not be parsed
- the document data is in an unsupported format
- the URI reference is incomplete or incorrect
- the URI reference is no longer valid (i.e., the server hosting
the data might be down)
- or any other job processing error
In this case, the Printer, depending on the error, can set the "job-
state", "job-state-reasons", or "job-state-message" to some
appropriate value.
3.2 Printer Operations
3.2.1 Get-Operations Operation
The client uses this operation to query a specific implementation for
a list of supported operations. All implementations MUST support this
operation because some of the IPP operations defined in this
specification are OPTIONAL.
3.2.1.1 Get-Operations Request
The Get-Operations Request has no input parameters.
3.2.1.2 Get-Operations Response
The Printer returns the following output parameters as part of the
Get-Operations Response:
Target Printer ("printer-uri"):
The URI of the target printer.
Supported Operations ("supported-operations"):
A list of the operations that this implementation supports
(including all MANDATORY operations). The values are taken from
the following set: 'Get-Operations', 'Print-Job', 'Print-URI',
'Validate-Job', 'Create-Job', 'Get-Jobs', 'Get-Attributes',
'Send-Document', 'Send-URI', and 'Cancel-Job'.
Note: Since this list contains all MANDATORY operations ('Get-
Operations', 'Print-Job', 'Validate-Job', 'Get-Jobs', 'Get-
Attributes', and 'Cancel-Job'), this output parameter will never
be empty.
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3.2.2 Print-Job Operation
When an end user desires to submit a print job with only one Document,
the client sends a Print-Job Request to a Printer and receives a
Print-Job Response from that Printer. The information in a Print-Job
Request (along with any default information associated with the
Printer) is sufficient for the Printer to create a Job object and then
process that Job. A Print-Job operation differs from a Print-URI
operation in that a Print-Job operation contains the document data to
be printed and a Print-URI operation only contains a reference to the
document data.
3.2.2.1 Print-Job Request
The following input parameters are part of the Print-Job Request:
"printer-uri" (uri):
The URI of the target printer.
"job-name" (name):
This optional parameter is supplied by the client. If it is not
supplied by the client, the Printer generates a name (see Section
4.3.3).
"best-effort" (boolean):
This parameter identifies the clients desire to accept best
effort printing or not. Best effor printing allows a job to be
printed even though there might be a conflict between what a
client requests in a create request and what a Printer supports.
This is a MANDATORY parameter. The value 'true' indicates that a
"best effort attempt to print the Job" is acceptable. If a
Printer does not support some of the client supplied Job Template
attributes or values, the Printer might have to ignore or
substitute attributes or values. The value 'false' indicates
that a best effort attempt to print the Job is not acceptable;
total fidelity to client supplied attributes and values is
required. In this case, the client is requesting that the Job be
printed exactly as specified, and if that is not possible the the
Job must be rejected rather than processed incorrectly. A client
may query the Printer's MANDATORY "best-effort-supported"
attribute to determine if either type of best effort printing (or
both) are supported. The request is rejected outright if either
the Printer's "best-effort-supported" attribute is set to only
'true' and the client supplies a value of 'false' or the
Printer's "best-effort-supported" attribute is set to only
'false' and the client supplies a value of 'true'.
Job Template Attributes:
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An optional set of Job Template attributes as defined in section
4.2. If the client supplies no Job Template attributes in the
Print-Job Request, the Printer uses its default value attributes
when processing the job.
Document Attributes
The client optionally supplies the "document-name" and "document-
format" attributes. If "document-name" is not supplied, the
Printer generates a name for the Document. If "document-format"
is not supplied, the Printer assumes that the document data is in
a format that this acceptable to the Printer.
ISSUE: Should "document-name" be a parameter and document-format
just be a Job Template attribute?
Document Content:
The client supplies the document data to be processed.
The simplest Print-Job Request consists of just the Document Content
and nothing else. In this case, the Printer creates a new Job object
with no associated Job Template attributes and the job contains a
single Document. The Printer also generates a name for the Document
and for the Job.
When a Printer receives a Print-Job Request, the Printer either
accepts or rejects the request. The Printer accepts the Print-Job
Request and creates a Job object if it is able to accept all Job
Template attributes in the request. The Printer rejects the request
and does not create a Job object if the Printer rejects any Job
Template attribute in the request. There are six cases to consider
when accepting or rejecting Job Template attributes:
1. The client supplies a Job Template attribute named "xxx" and the
value supplied by the client is among the values supported by the
Printer (i.e., is among the values of the Printer's "xxx-
supported" attribute): The "xxx" Job Template attribute is
accepted. The Printer creates the Job object and associates the
"xxx" attribute with the new Job object using the value supplied
by the client.
2. The client supplies a Job Template attribute but the attribute
is syntactically bad: The Printer rejects the job and returns the
attribute in the "unsupported-attributes" output parameter.
3. The client supplies a Job Template attribute and the attribute
value is not among the values supported by the Printer or the
Printer does not support the attribute at all: This case depends
on the value of the "best-effort' parameter. If the client
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supplies a value of 'false'the Printer SHALL reject the Job and
return the 'client-error-attribute-unsupported" error code and
the unsupported attribute in the "unsupported-attributes " output
parameter. If the client supplies a "best-effort" value of
'true' the Printer SHALL accept the Job either ignore unsupported
attributes or substitute supported values for all unsupported
values supplied by the client. In this case, if everything else
is ok, the Printer returns a "successful-ok-ignored-or-
substituted-attributes" status code. The client could later
query the Job object to find which of the Job attributes had been
ignored or substituted.
ISSUE: Does the above satisfy Jim W.'s issue about persistence of
the best effort value?
5. The client does not supply a Job Template attribute that is
supported by the Printer:: If all other attributes are
acceepted, the Printer accepts the request and creates the Job
object, the Printer does not associate the attribute with the new
Job object. When the Printer processes that Job, the Printer uses
the behavior implied by the default value Printer attribute as
set at the time of Job processing (not Job creation). In other
words, these rules allow a client to submit a Job with no Job
Template attribute and as the Printer processes the Job, the
Printer uses its the default value attribute in place of the
missing Job Template attribute. Suppose the Printer were to
associate the Printer's default value is with the Job at creation
time for an attribute which was not supplied by the client. A
later query of the Job object would reveal a set of Job object
attributes and neither the Printer nor the end user would be able
to tell the difference between a Job attribute that is an
"override PDL" attribute (supplied by the client) and another
which is a "default value" attribute (supplied by the printer).
6. Neither the client supplies an attribute nor the Printer
supports the attribute: : The Printer accepts the Job, however,
as far as IPP is concerned, the result of processing that Job
(with respect to the missing attributes) is undefined.
In many cases though, this case represents a legacy environment,
and even without IPP attributes, the Job will be processed
successfully. For example, the document data might have been
generated by a device-specific printer driver that formats the
job and emits a data stream (a stream of PDL) that is finely
tuned for the intended output device and its internal
interpreter. But, neither the output device nor the printer
driver are aware of the IPP protocol. However, an intermediate
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process, which is IPP aware, is able to submit the job and make
sure that it is delivered to the output device, yet be unaware of
all the Job Template attributes that might possibly be supported.
3.2.2.2 Print-Job Response
The Printer SHALL return to the client the following output parameters
as part of the Print-Job Response:
"job-uri" (uri):
A URI which the client SHALL use for all other operations on this
Job
Job Status Attributes:
This includes the following Job attributes: "job-name", "job-
state", and "job-state-reasons". The value of each attribute is
taken from a "snapshot" of the new Job object sometime after the
time the Printer receives the print request until just prior to
returning the response to the client. Since the "job-state-
message" attribute is OPTIONAL, it MAY be included in the
response, but it is NOT REQUIRED.
Note: Since any printer state information which affects a job's
state is reflected in the "job-state" and "job-state-reasons"
attributes, it is sufficient to return only these attributes and
no specific printer status attributes.
Unsupported Attributes:
This is a set of attributes and attribute values that are
unsupported. This output parameter is only returned in the
response if the status code indicates that there was such an
error.
The simplest response consists of the just the job identifier ("job-
uri") and Job Status attributes output parameters with a status code
of "successful-ok".
3.2.3 Print-URI Operation
This operation is identical to the Print-Job operation (section 3.2.2)
except that a client supplies a URI reference to the document data
using the "document-uri" (uri) input parameter rather than including
the document data itself. It is up to the IPP server to interpret the
URI and subsequently "pull" the document from the source referenced by
the URI string.
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3.2.4 Validate-Job Operation
This operation is similar to the Print-Job operation (section 3.2.2)
except that a client supplies no document data and the Printer
allocates no resources (i.e., it does not create a new Job object) to
process the job. This operation is used only to verify capabilities
of a printer object against whatever input parameters are supplied in
the Validate-Job request. There is no "job-uri" output parameter
returned in the Validate-Job Response. If the client supplies a
"document-uri" input parameter, the Printer SHOULD only validate the
syntax of the URI rather than follow the reference and validate the
contents of the reference. The Printer may choose to validate the
reference, however, later at job processing time, the reference will
need to be validated yet again. If all is well, the Printer returns
the status code "successful-ok".
3.2.5 Create-Job Operation
This operation is similar to the Print-Job operation (section 3.2.2)
except that a client supplies no document data or any reference to
document data in the Create-Job request. This operation is followed
by one or more Send-Document or Send-URI operations. If a Printer
object supports the Create-Job operation, it MUST also support either
the Send-Document operation or the Send-URI operation or both. Since
a client can use the Get-Operations operation, a client SHOULD NOT
attempt to use an unsupported operation.
3.2.6 Get-Attributes Operation
The Get-Attributes operation allows a client to obtain information
from a Printer object. The client supplies as an operation parameter
the set of attribute names and/or attribute group names that the
requester is interested in. The Printer returns a corresponding
attribute set in the response with the appropriate attribute values
filled in for each requested attribute (either explicitly named in the
request or implicitly included by naming an attribute group).
For Printers, the attribute groups include:
- 'job-template': all of the Job Template attributes that apply to
a Printer object (the last two columns of the table in Section
4.2).
- 'printer-description': the attributes specified in Section 4.5.
There are also special groups:
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- 'none': no attributes of the specified object. 'none' is
primarily useful in Get-Jobs, but can be used as a "ping" with
the Get-Attributes operation.
- 'all': all supported attributes
It is NOT REQUIRED that a Printer support all attributes belonging to
a group, however it is MANDATORY that each Printer implementation
understand all group names.
There is one group named 'document-attributes' which consists of the
Document Attributes described in section 4.4 ("document-name",
"document-format", and "document-uri"). These attributes may be
requested either individually or as a group. If any or all of these
attributes are requested, in the response, they are treated as multi-
valued attributes (one value for each Document in the Job). For
example, there are 5 Documents in the Job, then each returned Document
attribute MUST have 5 values: the set of first values from each
attribute correspond to the first Document, the set of second values
correspond to the second Document, and so on. In order to maintain
the same number of values in each returned attribute, if there is no
value for either the "document-format" or "document-uri" attributes, a
special "out of band" value of 'none' is returned in its place. This
out of band value requires an encoding described in the Protocol
Specification document [23].
For a complete example, consider a Job with 3 Documents and in the
Get-Attributes Request the group 'document-attributes' is requested.
The returned attributes (in the Get-Attributes Response) might look
like:
document-name = 'Document 1', 'Document 2', Document 3'
document-format = 'langPS', 'none', 'langPCL'
document-uri = ' ftp://some.domain.com/file1.ps', 'none', 'none'
3.2.6.1 Get-Attributes Request
The following input parameters are part of the Get-Attributes Request
when the request is directed to a Printer object:
"printer-uri" (uri):
The URI of the target printer.
"requested-attributes" (1setOf keyword) :
An optional set of attribute names (without values) or attribute
group names in whose values the requester is interested. If the
client omits this input parameter, the Printer SHALL respond as
if this input parameter had been supplied with a value of 'all'.
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"document-format" (enum) :
This input parameter is useful for determining the set of
supported attribute values which relate to the requested document
format. The Printer SHALL return only (1) those attributes that
are supported and (2) the attribute values that are supported for
the specified document format. By specifying the document
format, the client can get the Printer to eliminate the
attributes and values that are not supported for a specific
document format. For example, a Printer might have multiple
interpreters to support both 'langPS' (for PostScript) and
'langPCL' (for PCL) documents. However, for only one of those
interpreters might the Printer be able to support "number-up"
with values of 'one', 'two', and 'four'. For the other
interpreter it might be able to only support "number-up" with a
value of 'one'.
If the client omits this input parameter, the Printer SHALL
respond as if the input parameter had been set to the value of
the Printer's default value "document-format" attribute were
supplied. It is recommended that the client always supply a
value for document-format, since the Printer's default value for
document-format may be 'langAutomatic', in which case the
returned attributes and values are for the union of the document
formats that the Printer can automatically sense.
3.2.6.2 Get-Attributes Response
The Printer returns the following response parameters as part of the
Get-Attributes Response:
Requested Attributes:
This is a the set of requested attributes and their current
values. The Printer ignores (does not respond with) any
requested attribute which is not supported.
3.2.7 Get-Jobs Operation
The Get-Jobs operation allows a client to retrieve the list of Jobs
belonging to the target Printer object. The client may also supply a
list of Job attribute names or attribute group names. These Job
attributes will be returned for each Job that is returned.
This operation is like Get-Attributes, except that Get-Jobs operation
returns attributes from possibly more than one object (see the
description of attribute groups in section 3.2.6).
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3.2.7.1 Get-Jobs Request
The client submits the Get-Jobs request to a Printer URI.
The following input parameters are part of the Get-Jobs Request:
"printer-uri" (uri):
The URI of the target printer.
"limit" (integer):
This is an integer value that indicates a limit to the number of
Jobs returned. The limit is a "stateless limit" in that if the
limit is n then only the first n jobs are returned in the Get-
Jobs Response; there is no mechanism to allow for the "next" n
jobs. The limit applies across all Job States requested. For
example, if the limit if 50, and there are 75 spooled jobs, only
the first 50 jobs are returned; the other 25 jobs are not
returned.
"requested-attributes" (1setOf keyword):
An optional set of Job attribute names or attribute groups names
in whose values the requester is interested. This set of
attributes is returned for each Job that is returned.. The
attribute group names are the same as for the Get-Attributes
operation for the Job object. If the client omits this input
parameter, the Printer SHALL respond as if this input parameter
had been supplied with a value of " 'job-uri'.
3.2.7.2 Get-Jobs Response
The Printer SHALL return the following output parameters as part of
the Get-Jobs Response:
Requested Attributes:
The result includes zero or more Job objects each with zero or
more attributes. Jobs are returned in the following order: First
all active Jobs (Jobs in the 'pending', 'processing', 'pending-
held', and 'processing-stopped' states) are returned oldest to
newest (with respect to expected completion time) followed by all
completed Jobs (Jobs in the 'completed', 'aborted', or 'canceled'
states) newest to oldest (with respect to actual completion
time). Jobs that are in the 'pending-held' state SHALL appear in
their position as if they were 'pending' (otherwise, a user might
be confused by Jobs that move from 'pending-held' to 'pending' as
seeming to jump ahead in the queue).
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3.3 Job Operations
3.3.1 Send-Document Operation
Once a Job object has been created using a Create-Job operation
(returning a "job-uri"), a client directs a Send-Document operation to
the newly create Job object. The operation adds a new Document to the
Job object. An entire document MUST be sent in a single Send-Document
Request.
3.3.1.1 Send-Document Request
The client submits the request to a Job URI.
The following abstract data types are part of the Send-Document
Request:
"job-uri" (uri):
The URI of the target Job.
Document Attributes:
An optional set of Document Description attributes (section 4.4).
Last Document Flag ("last-document"):
This is a boolean flag that is set to 'true' if this is the last
Document for the Job.
Document Content:
The client supplies the document data.
3.3.1.2 Send-Document Response
The following output parameters are part of the Send-Document
Response:
Job Status:
(see section 3.2.2.2)
Unsupported Attributes:
(see section 3.2.2.2)
3.3.2 Send-URI Operation
This operation is identical to the Send-Document operation (see
section 3.3.1) except that a client supplies a URI reference
("document-uri") rather than the document data itself. It is up to
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the IPP server to interpret the URI and subsequently "pull" the
document from the source referenced by the URI string.
3.3.3 Cancel Job Operation
This operation allows a user to cancel one specific Print Job any time
after the print job has been established on the Printer. Some pages
may be printed before a job is terminated if printing has already
started when the Cancel Job operation is received. The Printer
determines via the security layer (authentication) and administrative
policy set outside the scope of IPP (authorization) whether or not to
allow the Cancel-Job operation.
3.3.3.1 Cancel-Job Request
The client submits the request to a Job URI.
The following abstract data types are part of the Cancel Job Request:
"job-uri" (uri):
The URI of the target Job.
"message" (text):
Optional message to the operator
3.3.3.2 Cancel-Job Response
There are no output parameters other Cancel Job Response other than
the Status Code and optional Status Message.
3.3.4 Get-Attributes Operation
The Get-Attributes operation allows a client to obtain information
from a Job object and it is almost identical to the Get-Attributes
operation for a Printer object (see section 3.2.6). The only
differences are that the operation is directed at a Printer URI rather
than a Job URI and there is no Document Format input parameter used
for querying a Job object.. In an input parameter, the client supplies
the set of attribute names and/or attribute group names that the
requester is interested in.
3.3.4.1 Get-Attributes Request
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4. Object Attributes
This section describes the attributes with their corresponding
syntaxes and values that are part of the IPP model. The sections below
show the objects and their associated attributes which are included
within the scope of this protocol. Many of these attributes are
derived from other relevant specifications:
- ISO/IEC 10175 DPA (Final, June 1996) [5]
- RFC 1759 Printer MIB (Proposed Standard, May 1995) [1]
- Internet-Draft: Printer MIB (Draft Standard in progress, July
1997) [29]
- Internet-Draft: Job Monitoring MIB (I-D in progress, June 1997)
[27]
Each attribute is uniquely identified in this document using a
"keyword" (see section 10.2.1). The keyword is included in the
section header describing that attribute. Not only are attributes
uniquely identified with keywords, some attributes are defined to have
a syntax which is a set of keywords.
4.1 Attribute Syntaxes
The following table shows the basic syntax types that a client and
server SHALL be able to handle.
text: a sequence of characters, length: 0 to 4095, where each
character is a member of the UCS-2 coded character set.. This
syntax type is used for free form human readable text intended
for human consumption. The default encoding for attributes of
type "text" is the UTF8 encoding rules. However, if the
attribute "content-char-set" is set to a value of type "char-set"
then that value describes the encoding rules used for text
attributes.
name: this is the same a "text" except that the sequence of
characters is of length 1 to 255 This syntax type is used for
referencing some object or entity via a user-friendly string,
such as a Printer name, a document name, a user name, or a host
name.
keyword: a sequence of characters, length: 1 to 255, containing
only the characters ASCII lowercase letters ("a" - "z"), ASCII
digits ("0" - "9"), hyphen ("-"), dot ("."), and underscore
("_"). The first character MUST be an ASCII lowercase letter.
This syntax type is used for enumerating semantic identifiers of
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entities in the abstract protocol (specified in this document).
These entities can be attribute names or values of attributes.
When a keyword is used to represent an attribute (its name), it
MUST be unique within the full scope of IPP objects and
attributes. When a keyword is used to represent a value of an
attribute, it MUST be unique just within the scope of that
attribute. That is, the same keyword can not be used for two
different values within the same attribute to mean two different
semantic ideas. However, the same keyword can be used across two
or more attributes, representing different semantic ideas for
each attribute.
enum: an enumerated integer value that is in the range from -2**31
to 2**31 - 1. Each value has an associated keyword name. Each
attribute (whose syntax is enum) enumerates the values that are
defined for the attribute. The enum type is used for attributes
for which there are enum values assigned by other standards, such
as SNMP MIBs. A number of attribute enum values in this
specification are also used for corresponding attributes in the
IETF Printer MIB [1] and the Job Monitoring MIB [27]. Enums are
not used for attributes to which the system administrator may
assign values. Values in the range 2**30 to 2**31 - 1 are
reserved for private or experimental use. Implementers are
warned that use of such values may conflict with other
implementations. Implementers are encouraged to request
registration of enum values following the procedures in Section
6.
uri: a sequence of characters as defined in rfc1738 and rfc1808.
This syntax type is used for carrying Universal Resource
Identifiers.
uriScheme: a sequence of characters representing the URI Scheme.
These include 'http' for HTTP schemed URIs (e.g., http://...),
and 'ftp' for FTP schemed URIs (e.g., ftp://...).
human-language: a standard identifier for human language and
optionally a country. The values for this syntax type are taken
from RFC 1766 [26]. RFC 1766 does not have provision for
expressing the coded character set component of a locale. The
"content-char-set" attribute contains a value which represents
the encoding rules used. If "content-char-set" is not supported,
the coded character set used in the IPP protocol MUST be UTF-8
[28].
char-set: a standard identifier the character set used in the
encoding of attributes of type "text". The values for this syntax
type are taken from RFC 2130 [31].
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octetString: a sequence of octets. This syntax type is used for
opaque data, such as the document-content.
boolean: two values of 'true' and 'false'. This syntax type is
like a keywordSet, but there are only two values. Note: An
application might use a checkbox for an attribute with this
syntax type.
integer: an integer value that is in the range from -2**31 to
2**31 - 1. Each attribute specifies the range constraint
explicitly if the range is different from the full range of
possible integer values (e.g., 0 - 100 for the "job-priority"
attribute).
dateTime: a standard, fixed length representation of date and time
as defined in RFC 1514 [32] and RFC 1903 [33].
resolution: a special syntax used only for "printer-resolution"
and "printer-resolution-supported" It consists of 3 parts: a
cross feed direction resolution (positive integer value), a feed
direction resolution (positive integer value) and a units value.
All these are taken from the Printer MIB [1] suggested values.
1setOf X: 1 or more values of type X. This syntax type is used
for multi-valued attributes, whose value is a set of values.
Note: The syntax type is called "1setOf" to indicate that set of
values SHALL NOT be empty (a set of size 0).
rangeOf X: a range of value of type X. This syntax type is used
for ordered values (numeric, lexical, etc.) such as integers.
4.1.1 Attribute Extensibility
This document uses prefixes to the "keyword" and "enum" basic
syntax type in order to communicate extra information to the reader
through its name. This extra information need not be represented in
an implementation because it is unimportant to a client or Printer.
The table below describes the prefixes and their meaning.
"type1": The IPP standard must be revised to add a new keyword or
a new enum. No private keywords or enums are allowed.
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"type2": Implementers can, at any time, add new keyword or enum
values by proposing them to the IPP working group for
registration (or an IANA-appointed registry advisor after the IPP
working group is no longer certified) where they are reviewed for
approval. IANA keeps the registry.
"type3": Implementers can, at any time, add new keyword and enum
values by submitting a registration request directly to IANA, no
IPP working group or IANA-appointed registry advisor review is
required.
"type4": Anyone (system administrators, system integrators, site
managers, etc.) can, at any time, add new installation-defined
values (keywords or new enum values) to a local system. Care
SHOULD be taken by the implementers to see that keywords do not
conflict with other keywords defined by the standard or as
defined by the implementing product. There is no registration or
approval procedure for type 4 keywords.
By definition, each of the four types above assert some sort of
registry or review process in order for extensions to be considered
valid. Each higher level (1, 2, 3, 4) tends to be decreasingly less
stringent than the previous level. Therefore, any typeN value MAY be
registered using a process for some typeM where M is less than N,
however such registration is NOT REQUIRED. For example, a type4 value
MAY be registered in a type 1 manner (by being included in a future
version of an IPP specification) however it is NOT REQUIRED.
This specification defines keyword and enum values for all of the
above types, including type4 keywords.
For private (unregistered) keyword extensions, implementers SHOULD use
keywords with a suitable distinguishing prefix, such as "xxx-" where
xxx is the (lowercase) fully qualified company name registered with
IANA for use in domain names [30].
Note: RFC 1035 [30] indicates that while upper and lower case letters
are allowed in domain names, no significance is attached to the case.
That is, two names with the same spelling but different case are to be
treated as if identical. Also, the labels in a domain name must
follow the rules for ARPANET host names: They must start with a
letter, end with a letter or digit, and have as interior characters
only letters, digits, and hyphen. Labels must be 63 characters or
less. Lables are separated by the "." character.
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For private (unregistered) enum extension, implementers SHOULD use
values in the reserved integer range (see "enum").
4.2 Job Template Attributes
Job Template attributes describe job processing behavior. Take for
example, a generic Job Template attribute called "xxx":
1. "xxx" is optionally supplied by the client in a create request.
If "xxx" is supplied, the client is specifying that the Printer
SHALL apply a specific job processing behavior to this job while
processing the Job. When "xxx" is not supplied by the client,
the Printer applies the default job processing behavior.
2. "xxx-supported" is a Printer attribute that describes which
behaviors are supported by a Printer. "xxx-supported" is a
CONDITIONALLY MANDATORY attribute, that is the "xxx-supported"
attribute is MANDATORY if the Printer is capable of realizing two
or more of the behaviors associated with the attribute and its
values. A client can query the Printer and find out what
behaviors are supported by inspecting the values of the "xxx-
supported" attribute.
3. The Printer also supports a default value attribute named "xxx".
This default value attribute describes what will be done when no
other job processing information is supplied by the client
(either explicitly as an IPP attribute in the create request or
implicitly as an embedded instruction within the job data).
Along with the supported attribute, the default value attribute
is also CONDITIONALLY MANDATORY. However, if the Printer
supports either the "xxx" default value attribute or the "xxx-
supported" attribute, the Printer MUST support both.
4. If a client application wishes to present an end user with a
list of supported and default values from which to choose, the
client program SHOULD query the Printer for the supported and
default value attributes. The values that the client then
supplies in the create request will all fall within the supported
values of the Printer. When querying the Printer, the client MAY
enumerate each attribute by name in the Get-Attributes Request,
or the client MAY just name the "job-template" group in order to
get the complete set of supported and default value attributes
which are supported.
The "job-priority" attribute is an example of a Job Template
attribute. It is an integer in the range from 1 to 100. A client can
query the Printer for the "job-priority-supported" attribute and the
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"job-priority" default value attribute. The supported attribute
contains a range of supported priority values which is equal to or
smaller than the maximum range of 1 to 100. The default value
attribute contains the job priority value that will be used for a new
job if the client does not supply one in the create request. If the
client does supply the "job-priority" attribute, the Printer validates
the value to make sure that it falls within the range of supported
values. If the client-supplied value is supported, the Job object is
created and the "job-priority" attribute is populated with that value.
The Job object, when queried, returns the value supplied by the
client. If the client does not supply a "job-priority" value in the
create request, the Job object is created, but no "job-priority"
attribute is associated with the Job. The client queries the
Printer's default value "job-priority" value to find out at what
priority the job will be processed.
The table below summarizes the names, relationships, and conformance
requirements for all Job Template attributes. The following general
rules apply to implementation requirements:
1. In a create request, all Job Template attributes are optionally
supplied by the client.
2. In a Printer Object, all supported attributes ("xxx-supported")
are CONDITIONALLY MANDATORY.
3. All Printer default value attributes ("xxx") are CONDITIONALLY
MANDATORY.
Note: If the Printer implements either the default value attribute
or the supported values attribute, the Printer MUST also
implement the other and vice versa.
The table only shows exceptions to the above rules. The first column
of the table (Job) shows the name and syntax for each Job Template
attribute in the Job object.. All of the attributes in the first
column make up the "job-template" group. The last two columns show
the name and syntax for each Job Template attribute in the Printer
object (the default value attribute and the supported attribute). A
"No" in the table means the Printer SHALL NOT support the attribute.
A "MAN" indicates that it is MANDATORY that the Printer support the
attribute.
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+-------------------+----------------------+----------------------+
| Job |Printer: Default Value| Printer: Supported |
+===================+======================+======================+
| job-sheets | job-sheets |job-sheets-supported |
| (type4 keyword) | (type4 keyword) |(1setOf type4 keyword)|
| | | |
+-------------------+----------------------+----------------------+
| notify-events | notify-events | notify-events- |
|(1setOf |(1setOf type2 keyword)| supported |
| type2 keyword) | |(1setOf type2 keyword)|
+-------------------+----------------------+----------------------+
|notify-addresses | No |notify-addresses |
|(1setOf uri) | |-supported |
| | |(1setOf uriScheme) |
+-------------------+----------------------+----------------------+
| job-priority | job-priority |job-priority-supported|
| (integer 1-100) | (integer 1-100) |(rangeOf integer |
| | | 1-100) |
+-------------------+----------------------+----------------------+
| job-hold-until | job-hold-until | job-hold-until- |
| (type4 keyword) | (type4 keyword) | supported |
| | |(1setOf type4 keyword)|
+-------------------+----------------------+----------------------+
|multiple-document- |multiple-document- |multiple-document- |
| handling | handling |handling-supported |
| (type2 keyword) | (type2 keyword) |(1setOf type2 keyword)|
+-------------------+----------------------+----------------------+
| media | media | media-supported |
| (type4 keyword) | (type4 keyword) |(1setOf type4 keyword)|
| | | |
+-------------------+----------------------+----------------------+
| number-up | number-up | number-up-supported |
| (type3 keyword) | (type3 keyword) |(1setOf type3 keyword)|
| | | |
+-------------------+----------------------+----------------------+
| sides | sides | sides-supported |
| (type2 keyword) | (type2 keyword) |(1setOf type2 keyword)|
| | | |
+-------------------+----------------------+----------------------+
| printer-resolution| printer-resolution | printer-resolution- |
| (type2 enum) | (type2 enum) | supported |
| | |(1setOf type2 enum) |
+-------------------+----------------------+----------------------+
| print-quality | print-quality | print-quality- |
| (type2 enum) | (type2 enum) | supported |
| | |(1setOf type2 enum) |
+-------------------+----------------------+----------------------+
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| finishings | finishings | finishings-supported |
|(1setOf type2 enum)|(1setOf type2 enum) |(1setOf type2 enum) |
| | | |
+-------------------+----------------------+----------------------+
| copies | copies | copies-supported |
| (integer: 1 - MAX)| (integer: 1 - MAX) | (rangeOf integer |
| | | 1- MAX) |
+-------------------+----------------------+----------------------+
| document-format | document-format | document-format- |
| (type2 enum) | (type2 enum) | supported |
| | |(1setOf type2 enum) |
+-------------------+----------------------+----------------------+
| compression | No | compression-supported|
| (type3 keyword) | |(1setOf type3 keyword)|
| | | |
+-------------------+----------------------+----------------------+
| job-k-octets | No |job-k-octets-supported|
| (integer) | | (rangeOf integer) |
| | | |
+-------------------+----------------------+----------------------+
| job-impressions | No | job-impressions- |
| (integer) | | supported |
| | | (rangeOf integer) |
+-------------------+----------------------+----------------------+
| job-media-sheets | No | job-media-sheets- |
| (integer) | | supported |
| | | (rangeOf integer) |
+-------------------+----------------------+----------------------+
4.2.1 job-sheets (type4 keyword)
This attribute determines which if any banner page(s) SHALL be printed
with a job.
Standard values are:
'none': no job sheet is printed
'standard': one or more site specific standard job sheets are
printed, e.g. a single start sheet or both start and end sheet is
printed
To force no job sheets, the system administrator SHALL set the
supported value to only 'none'. To force the use of banner pages, the
supported values SHALL not include 'none'. In this case, if a client
requests 'none', the create request is rejected.
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Note: The effect of this attribute on jobs with multiple documents is
controlled by the "multiple-document-handling" job attribute (section
4.2.6).
4.2.2 notify-events (1setOf type2 keyword)
This attribute specifies the events for which the end user desires
some sort of notification. The "notify-addresses" attribute is used
to describe the destination addresses for these events.
Standard values are:
'none': the Printer SHALL not notify.
'all': the Printer SHALL notify when any of the events occur.
'job-completion': the Printer SHALL notify when the job containing
this value completes (i.e., enters the 'completed', 'canceled',
or 'aborted' state) with or without errors.
'job-problems': the Printer SHALL notify when this job has a
problem while this job is processing (i.e., when the Job moves
from the 'processing' to the 'processing-stopped' state or from
'pending' to 'pending-held'). Problems also can include any of
the "job-state-reasons" or "printer-state-reason" values.
ISSUE: All or none or some "xxx-reasons"??
'printer-problems': the Printer SHALL notify when this job is
affected by a Printer problem. This happens when the printer
enters the 'stopped' state while this job is in the 'pending',
'pending-held', 'processing', or 'processing-stopped' state. If
the Printer enters the 'stopped' state, the reason is in the
"printer-state-reasons" attribute.
ISSUE: Do you really need this last sentence. That is, should this
document state what information an implementation should use to
compose the notification message.
4.2.3 notify-addresses (1setOf uri)
This attribute describes both where (the address) and how (the
mechanism for delivery ) events are to be delivered. The Printer SHALL
use this attribute as the set of addresses and methods for sending
messages when an event occurs that the end user (job submitter) has
registered an interest in.
Standard uriScheme values are:
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'mailto': the Printer sends a text message via email to the
specified email address
'http': the Printer sends an HTML formatted message via an HTTP
POST method to the specified URI
'ftp': the Printer sends a text message via an FTP `append' command
to the specified remote file.
4.2.4 job-priority (integer(1:100))
This attribute specifies a priority for scheduling the Job. A higher
value specifies a higher priority. The value 1 indicates the lowest
possible priority. The value 100 indicates the highest possible
priority. Among those jobs that are ready to print, a Printer SHALL
print all jobs with a priority value of n before printing those with a
priority value of n-1 for all n. The mapping of vendor-defined
priority over this range is implementation-specific.
4.2.5 job-hold-until (type4 keyword)
This job attribute specifies the named time period during which the
Job print job SHALL become a candidate for printing.
Standard values for named time periods are:
'no-hold': immediately, if there are not other reasons to hold the
job.
'day-time': during the day.
'evening': evening
'night': night
'weekend': weekend
'second-shift': second-shift
'third-shift': third-shift (after midnight)
An administrator SHALL associate allowable print times with a named
time period (by means outside IPP 1.0). An administrator is
encouraged to pick names that suggest the type of time period.
If the value of this attribute specifies a time period that is in the
future, the Printer SHALL add the 'job-hold-until-specified' value to
the job's "job-state-reasons" attribute, move the job to the 'pending-
held' state, and SHALL NOT schedule the job for printing until the
specified time-period arrives. When the specified time period
arrives, the Printer SHALL remove the 'job-hold-until-specified' value
from the job's "job-state-reason" attribute and, if no other job
reasons that keep it in the 'pending-held' state remain, the Printer
SHALL consider the job as a candidate for processing by moving the job
to the 'pending' state.
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If this job attribute value is the named value 'no-hold', or specified
time period is in effect has already started , the job SHALL be a
candidate for processing immediately.
4.2.6 multiple-document-handling (type2 keyword)
This job attribute is relevant only if a job consists of two or more
documents. It controls finishing operations, and job-sheet placement.
When the copies attribute exceeds 1, it also controls the order of
documents..
Standard values are:
'single-document': If the files for the job are a and b, then files
a and b SHALL be treated as a single document for finishing
operations. Also, there SHALL be no slip sheets between files a
and b and the Printer SHALL NOT force each document to start on a
new page or new media sheet. If more than one copy is made, the
ordering SHALL be a, b, a, b, ...., and the Printer SHALL force
each copy to start on a new sheet.
'separate-documents-uncollated-copies': If the files for the job
are a and b, then each file SHALL be treated as a single document
for finishing operations. Also, a client may specify that a slip
sheet be placed between files a and b and the Printer shall force
each document copy to start on a new sheet. If more than one
copy is made, the ordering SHALL be a, a, b, b, ....
'separate-documents-collated-copies': If the files for the job are
a and b, then each file SHALL be treated as a single document for
finishing operations. Also, a client may specify that a slip
sheet be placed between files a and b. If more than one copy is
made, the ordering SHALL be a, b, a, b, ...., and the Printer
shall force each document copy to start on a new sheet
4.2.7 media (type4 keyword)
This job attribute identifies the medium that the Printer uses for all
pages of the Job.
The values for "media" include medium-names, medium-sizes, input-trays
and electronic forms so that one attribute specifies the media. If a
printer allows a client to specify a medium name as the value of this
attribute, such a medium name implicitly selects an input-tray that
contains the specified medium. If a printer allows a client to
specify a medium size as the value of this attribute, such a medium
size implicitly selects a medium name which in turn implicitly selects
an input-tray that contains the medium with the specified size. If a
printer allows a client to specify an input-tray as the value of this
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attribute, such an input-tray implicitly selects the medium that is in
that input-tray at the time the job prints. This case includes manual-
feed input-trays. If a printer allows a client to specify an
electronic form as the value of this attribute, such an electronic
form implicitly selects a medium-name which in turn implicitly selects
an input-tray that contains the medium specified by the electronic
form. The electronic form also implicitly selects an image that the
Printer SHALL merge with the data from the document as its prints each
page.
Standard values are (taken from ISO DPA and the Printer MIB) and are
listed in section 13.
4.2.8 number-up (type3 keyword)
This job attribute specifies the number of source page-images to
impose upon a single side of an instance of a selected medium.
Standard values are:
'none': The Printer SHALL not include any embellishments and SHALL
place one logical page on a single side of an instance of the
selected medium without any translation, scaling, or rotation.
'one': The Printer SHALL place one logical page on a single side of
an instance of the selected medium (MAY add some sort of
translation, scaling, or rotation).
'two': The Printer SHALL place two logical pages on a single side
of an instance of the selected medium (MAY add some sort of
translation, scaling, or rotation).
'four': The Printer SHALL place four logical pages on a single side
of an instance of the selected medium (MAY add some sort of
translation, scaling, or rotation).
This attribute primarily controls the translation, scaling and
rotation of page images, but a site may choose to add embellishments,
such as borders to each logical page.
4.2.9 sides (type2 keyword)
This attribute specifies how source page-images are to be imposed upon
the sides of an instance of a selected medium.
The standard values are:
'one-sided': imposes each consecutive source page-image upon the
same side of consecutive media sheets.
'two-sided-long-edge': imposes each consecutive pair of source
page-image upon front and back sides of consecutive media sheets,
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such that the orientation of each pair of source-pages on the
medium would be correct for the reader as if for binding on the
long edge. This imposition is sometimes called 'duplex'.
'two-sided-short-edge': imposes each consecutive pair of source
page-image upon front and back sides of consecutive media sheets,
such that the orientation of each pair of source-pages on the
medium would be correct for the reader as if for binding on the
short edge. This imposition is sometimes called 'tumble' or
'head-to-toe'.
'two-sided-long-edge', 'two-sided-short-edge', 'tumble', and 'duplex'
all work the same for portrait or landscape. However 'head-to-toe' is
'tumble' in portrait but 'duplex' in landscape. 'head-to-head' also
switches between 'duplex' and 'tumble' when using portrait and
landscape modes.
4.2.10 printer-resolution (resoultion)
This attribute identifies the resolution that Printer uses for a
certain Job.
The value is a special type consisting of a pair of integers and a
value which specifies the units for the two integers. The three
values are the same as those specified in the draft-ietf-
printmib-mib-info-02.txt as prtMarkerAddressabilityFeedDir (the
resolution in the feed direction),
prtMarkerAddressabilityXFeedDir (the resolution in the cross feed
direction), and prtMarkerAddressabilityUnit (the units of the
first two values, namely dots per inch and dots per centimeter).
4.2.11 print-quality (type2 enum)
This attribute specifies the print quality that the Printeruses for a
certain Job.
The standard values are:
'draft' (3): lowest quality available on the printer
'normal' (4): normal or intermediate quality on the printer
'high' (5): highest quality available on the printer
4.2.12 finishings (1setOf type2 enum)
This attribute identifies the finishing operations that the Printer
uses for each copy of each printed document in a particular Job. For
Jobs with multiple documents, the "multiple-document-handling"
attribute determines what constitutes a _copy_ for purposes of
finishing.
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Standard values are:
'none'(3): Perform no finishing
'staple'(4): Bind the document(s) with one or more staples. The
exact number and placement of the staples is site-defined.
'staple-top-left'(5): Place one or more staples on the top left
corner of the document(s).
'staple-bottom-left'(6): Place one or more staples on the bottom
left corner of the document(s).
'staple-top-right'(7): Place one or more staples on the top right
corner of the document(s).
'staple-bottom-right'(8): Place one or more staples on the bottom
right corner of the document(s).
'saddle-stitch'(9): Bind the document(s) with one or more staples
(wire stitches) along the middle fold. The exact number and
placement of the stitches is site-defined.
'edge-stitch'(10): Bind the document(s) with one or more staples
(wire stitches) along one edge. The exact number and placement
of the staples is site-defined.
'punch'(11): This value indicates that holes are required in the
finished document. The exact number and placement of the holes is
site-defined The punch specification MAY be satisfied (in a
site- and implementation-specific manner) either by
drilling/punching, or by substituting pre-drilled media.
'cover'(12): This value is specified when it is desired to select
a non-printed (or pre-printed) cover for the document. This does
not supplant the specification of a printed cover (on cover stock
medium) by the document itself.
'bind'(13): This value indicates that a binding is to be applied
to the document; the type and placement of the binding is site-
defined."
4.2.13 copies (integer(1:2**31 - 1))
This attribute specifies the number of copies of the job to be
printed.
Note: The effect of this attribute on job with multiple documents is
controlled by the "multiple-document-handling" job attribute (section
4.2.6).
4.2.14 document-format (type2 enum)
This attribute defines the document format for each Document in a Job.
The standard values for this attribute are enums. Since the complete
list is rather long, the full enumeration of standard values is found
in section 12 APPENDIX C: "document-format" enum values.
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If the "document-format" is unknown for a certain document, the client
SHALL NOT supply the attribute in the create request or the Send-
Document Request.
4.2.15 compression (type3 keyword)
This attribute identifies compression algorithms used for compressed
document data.
ISSUE: Is this in the HTTP header and an attribute is compression
applied at both levels?
'none': no compression is used.
'zip':ZIP compression technology
`gzip' GNU zip compression technology described in RFC 1952.
'compress': UNIX compression technology
4.2.16 job-k-octets (integer(0:2**31 - 1))
This attribute specifies the total size of the job in K octets, i.e.,
in units of 1024 octets. The value SHALL be rounded up, so that a job
between 1 and 1024 octets SHALL be indicated as being 1, 1025 to 2048
SHALL be 2, etc.
Note: This attribute and the following two attributes ("job-
impressions" and "job-media-sheets") are not intended to be counters;
they are intended to be useful routing and scheduling information if
known. The Printer may try to compute the value if it is not supplied
in the create request. The Printer, however, might not be able to
compute this value at the time the Job is created. If not, the
Printer may support this attribute at any later time as it is able to
compute value.
ISSUE: What does this last sentence mean. Do we need to make the
distinction as to whether the printer computes this attribute
immediately as it is creates versus somewhat later?
4.2.17 job-impressions (integer(0:2**31 - 1))
This attribute specifies the total size of the job in impressions.
4.2.18 job-media-sheets (integer(0:2**31 - 1))
This attribute specifies the total size of the job in media-sheets.
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4.3 Job Description Attributes
The attributes in this section form the attribute group called "job-
description". The following table summarizes these attributes. The
third column indicates whether the attribute is a MANDATORY attribute.
If it is not MANDATORY, then it is OPTIONAL.
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+----------------------------+----------------------+----------------+
| Attribute | Syntax | MANDATORY? |
+----------------------------+----------------------+----------------+
| job-uri | uri | MANDATORY |
+----------------------------+----------------------+----------------+
| job-uri-user | uri | |
+----------------------------+----------------------+----------------+
| job-name | name | |
+----------------------------+----------------------+----------------+
| job-originating-user | name | MANDATORY |
+----------------------------+----------------------+----------------+
| job-originating-host | name | |
+----------------------------+----------------------+----------------+
| user-human-language | human-language | |
+----------------------------+----------------------+----------------+
| user-content-char-set | char-set | |
+----------------------------+----------------------+----------------+
| job-state | type1 enum | MANDATORY |
+----------------------------+----------------------+----------------+
| job-state-reasons | 1setOf type2 keyword | |
+----------------------------+----------------------+----------------+
| job-state-message | text | |
+----------------------------+----------------------+----------------+
| output-device-assigned | name | |
+----------------------------+----------------------+----------------+
| time-since-pending | milliseconds | MANDATORY |
+----------------------------+----------------------+----------------+
| time-since-processing | milliseconds | MANDATORY |
+----------------------------+----------------------+----------------+
| time-since-completed | milliseconds | MANDATORY |
+----------------------------+----------------------+----------------+
| number-of-intervening-jobs | integer | MANDATORY |
+----------------------------+----------------------+----------------+
| job-message-from-operator | text | |
+----------------------------+----------------------+----------------+
| job-k-octets-processed | integer | |
+----------------------------+----------------------+----------------+
| job-impressions-completed | integer | |
+----------------------------+----------------------+----------------+
| job-media-sheets-completed | integer | |
+----------------------------+----------------------+----------------+
ISSUE: Should time-since-xxx and number-of jobs be MANDATORY?
4.3.1 job-uri (uri)
This attribute contains the URI for the job. The Printer, on receipt
of a new job, generates a URI which identifies the new Job on that
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Printer. The Printer returns the value of the "job-uri" attribute as
part of the response to a create request. The precise format of a
job URI is implementation dependent.
4.3.2 job-uri-user (uri)
Similar to "job-uri", this attribute contains the URI referencing an
HTML page containing information about the Job.
4.3.3 job-name (name)
This attribute is the name of the job. It is a name that is more user
friendly than the "job-uri" attribute value. It does not need to be
unique. This is set to the value of the "job-name" input parameter in
the create request. However, if it is not supplied in the create
request, the Printer, on creation of the Job, SHALL generate a name.
The Printer can be generate the name using the name of the first
Document (the "document-name" attribute) if supplied or some other
piece of Job specific information.
4.3.4 job-originating-user (name)
This attribute specifies the user name of the person submitting the
print job. The Printer sets this attribute to the most authenticated
name that it can obtain from the protocol over which the operation was
received from the client.
4.3.5 job-originating-host (name)
This attribute identifies the originating host of the job. The Printer
sets this attribute to the most authenticated host name it can obtain
from the protocol over which the operation was received from the
client.
4.3.6 user-human-language (human-language)
This attribute identifies the human language and optionally the
country of the end user. The Printer sets this attribute to the most
reliable value it can obtain from the protocol over which the Print
operation was received from the client.
The Printer uses this attribute to determine the locale it SHOULD use
for localizing any text strings that it sends back to the end user.
These include status messages, text attributes, and notification
messages.
ISSUE: should we a statement about which attributes should be
localized. I would expect the text attributes set by the manufacturer
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would be localized. They are: job-state-message , printer-more-info-
manufacturer, printer-state-message, and printer-make-and-model. I
would expect text attribute set by a site would not be localized. They
are job-message-from-operator, printer-location, printer-description,
printer-message-from-the-operator. Should there be a separate text
type called localized-text for the 4 attributes mentioned in the
previous issue that can be localized. Should all "text" be localized
text? Unless we do something, the localization issue is left very
vague.
4.3.7 user-content-char-set (char-set)
This attribute identifies encoding character set for any text
attributes the client sends or desires to receive in IPP operations.
The Printer sets this attribute to the most reliable value it can
obtain from the protocol over which the Print operation was received
from the client. If this attribute is not supported, the value UTF-8
MUST be assumed. All clients and all servers MUST support UTF-8.
4.3.8 job-state (type1 enum)
This attribute identifies the current state of the job. Even though
the IPP protocol defines eight values for job states, implementations
only need to support those states which are appropriate for the
particular implementation. In other words, a Printer supports only
those job states implemented by the output device and available to the
Printer object implementation.
Standard values are:
'unknown'(2): The job state is not known, or its state is
indeterminate.
'pending'(3): The job is a candidate to start processing, but is
not yet processing.
'pending-held'(4): The job is not a candidate for processing for
any number of reasons but will return to the 'pending' state as
soon as the reasons are no longer present. The job's "job-state-
reason" attribute SHALL indicate why the job is no longer a
candidate for processing.
'processing'(5): Either:
1. the job is using, or is attempting to use, one or more
document transforms which include (1) purely software
processes that are interpreting a PDL, and (2) hardware
devices that are interpreting a PDL, making marks on a medium,
and/or performing finishing, such as stapling OR
2. the server has made the job ready for printing, but the
output device is not yet printing it, either because the job
hasn't reached the output device or because the job is queued
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in the output device or some other spooler, awaiting the
output device to print it.
When the job is in the 'processing' state, the entire job state
includes the detailed status represented in the printer's
"printer-state", "printer-state-reasons", and "printer-state-
message" attributes.
Implementations MAY include additional values in the job's "job-
state-reasons" attribute to indicate the progress of the job,
such as adding the 'job-printing' value to indicate when the
output device is actually making marks on paper. Most
implementations won't bother with this nuance.
ISSUE: Change to (but this must be synchronized with JMP)
'processing'(5): One of:
1. the job is using, or is attempting to use hardware devices
that are making marks on a medium, and/or performing
finishing, such as stapling OR
2. the job is using, or is attempting to use software processes
that are analyzing or interpreting a PDL without making marks
on a medium.
3. the server has made the job ready for printing, but the output
device is not yet printing it, either because the job hasn't
reached the output device or because the job is queued in the
output device or some other spooler, awaiting the output
device to print it.
'processing-stopped'(6): The job has stopped while processing for
any number of reasons and will return to the 'processing' state
as soon as the reasons are no longer present.
The job's "job-state-reason" attribute MAY indicate why the job
has stopped processing. For example, if the output device is
stopped, the 'printer-stopped' value MAY be included in the job's
"job-state-reasons" attribute.
NOTE - When an output device is stopped, the device usually
indicates its condition in human readable form locally at the
device. A client can obtain more complete device status remotely
by querying the printer's "printer-state", "printer-state-
reasons" and "printer-state-message" attributes.
'canceled'(7): The job has been canceled by a Cancel-Job operation
and is either (1) in the process of terminating or (2) has
completed terminating. The job's "job-state-reasons" attribute
SHOULD contain either the 'canceled-by-user' or 'canceled-by-
operator' value.
'aborted'(8): The job has been aborted by the system, usually
while the job was in the 'processing' or 'processing-stopped'
state.
'completed'(9): The job has completed successfully or with
warnings or errors after processing and all of the job media
sheets have been successfully stacked in the appropriate output
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bin(s). The job's "job-state-reasons" attribute SHOULD contain
one of: 'completed-successfully', 'completed-with-warnings', or
'completed-with-errors' values.
The final value for this attribute SHALL be one of: 'completed',
'canceled', or 'aborted' before the Printer removes the job
altogether. The length of time that jobs remain in the 'canceled',
'aborted', and 'completed' states depends on implementation.
The following figure shows the normal job state transitions.
+----> canceled
/
+----> pending --------> processing ---------+------> completed
| ^ ^ \
--->+ | | +----> aborted
| v v /
+----> pending-held processing-stopped ----+
Normally a job progresses from left to right. Other state transitions
are unlikely, but are not forbidden. Not shown are the transitions to
the 'canceled' state from the 'pending', 'pending-held', 'processing',
and 'processing-stopped' states.
4.3.9 job-state-reasons (1setOf type2 keyword)
This attribute provides additional information about the job's current
state, i.e., information that augments the value of the job's "job-
state" attribute.
Implementation of these values is OPTIONAL, i.e., a Printer NEED NOT
implement them, even if (1) the output device supports the
functionality represented by the reason and (2) is available to the
Printer object implementation. These values MAY be used with any job
state or states for which the reason makes sense. Furthermore, when
implemented, the Printer SHALL return these values when the reason
applies and SHALL NOT return them when the reason no longer applies
whether the value of the job's "job-state" attribute changed or not.
When the job does not have any reasons for being in its current state,
the Printer shall set the value of the job's "job-state-reasons"
attribute to 'none'.
NOTE - While values cannot be added to the 'job-state' attribute
without impacting deployed clients that take actions upon receiving
"job-state"values, it is the intent that additional "job-state-
reasons" values can be defined and registered without impacting such
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deployed clients. In other words, the "job-state-reasons" attribute
is intended to be extensible.
The following standard values are defined:
NOTE - For easy of understanding the order of the reasons is presented
in the order in which the reason is most likely to occur:
'none': There are no reasons for the job's current state.
'job-incoming': The CreateJob operation has been accepted by the
Printer, but the Printer is expecting additional SendDocument
operations and/or is accessing/accepting document data.
'job-outgoing': The Printer is transmitting the job to the output
device.
'job-hold-until-specified': The value of the job's "job-hold-
until" attribute specifies a time period that is still in the
future. The job SHALL NOT be a candidate for processing until
this reason is removed and there are no other reasons to hold the
job.
'resources-are-not-ready': At least one of the resources needed by
the job, such as media, fonts, resource objects, etc., is not
ready on any of the physical printer's for which the job is a
candidate. This condition MAY be detected when the job is
accepted, or subsequently while the job is pending or processing,
depending on implementation.
ISSUE: Change to job-hold-until-specified-time and job-hold-until-
resources-ready to make it clear that the job-state is pending-
held?.
'printer-stopped-partly': The value of the Printer's "printer-
state-reasons" attribute contains the value 'stopped-partly'.
'printer-stopped': The value of the Printer's "printer-state"
attribute is 'stopped'.
'job-printing': The output device is marking media. This value is
useful for Printers which spend a great deal of time processing
when no marking is happening and then want to show that marking
is now happening.
'job-cancelled-by-user': The job was cancelled by the user using
the CancelJob request, i.e., by a user whose name is the same as
the value of the job's "job-originating-user" attribute.
'job-cancelled-by-operator': The job was cancelled by the operator
using the CancelJob request, i.e., by a user whose name is
different than the value of the job's "job-originating-user"
attribute.
'job-completed-successfully': The job completed successfully.
'job-completed-with-warnings': The job completed with warnings.
'job-completed-with-errors': The job completed with errors (and
possibly warnings too).
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'logfile-pending ': The job's logfile is pending file transfer.
'logfile-transferring': The job's logfile is being transferred.
ISSUE: How does this protocol get a logfile transfer to occur? I
suggest we delete them.
4.3.10 job-state-message (text)
This attributes specifies supplemental information about the Job State
in human readable text.
4.3.11 output-device-assigned (name)
This attribute identifies the Output Device to which the Printer has
assigned this job. If an output device implements an embedded IPP
Printer, the Printer NEED NOT set this attribute. If a Print Server
implements a Printer, the value MAY be empty until the Printer assigns
an output device to the job.
4.3.12 time-since-pending (integer)
This attribute indicates the amount of time in milliseconds that has
passed since the Job was first put into the pending state..
4.3.13 time-since-processing (integer)
This attribute indicates the amount of time in milliseconds that has
passed since the Job first entered the processing state.
4.3.14 time-since-completed (integer)
This attribute indicates the amount of time in milliseconds that has
passed since the Job was completed.
4.3.15 number-of-intervening-jobs (integer(0:2**31 - 1))
This attribute indicates the number of jobs that are "ahead" of this
job in the current scheduled order. For efficiency, it is only
necessary to calculate this value when an operation is performed that
requests this attribute.
Note: This attribute is necessary since an end user may request just
their own jobs and they need some relative position indicator if there
are other jobs interspersed in the waiting list which are not returned
in the response or cannot be because of site security policy
restrictions.
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ISSUE: No longer possible to request an owners job, so may this
attribute isn't important now.
4.3.16 job-message-from-operator (text)
This attribute provides a message from an operator, system
administrator or "intelligent" process to indicate to the end user the
reasons for modification or other management action taken on a job.
4.3.17 job-k-octets-processed (integer(0:2**31 - 1))
This attribute specifies the number of octets completed in K octets,
i.e., in units of 1024 octets. The value SHALL be rounded up, so that
a job between 1 and 1024 octets SHALL be indicated as being 1, 1025 to
2048 SHALL be 2, etc.
Note: This attribute and the following two attributes ("job-
impressions-completed" and "job-sheets-completed") are intended to be
counters as in the Job Monitoring MIB [27]. That is, if the "job-
state" is 'processing' or 'processing-stopped', this value is intended
to contain amount of the job that has been processed to the time at
which the attributes are requested.
4.3.18 job-impressions-completed (integer(0:2**31 - 1))
This job attribute specifies the number of impressions completed. This
attribute is intended to be a counter as in the Job Monitoring MIB.
4.3.19 job-media-sheets-completed (integer(0:2**31 - 1))
This job attribute specifies the media-sheets completed. This
attribute is intended to be a counter as in the Job Monitoring MIB.
4.4 Document Attributes
This group of attributes describes the document data for the job. For
single-Document Jobs, they are supplied in the Print-Job or Print-URI
requests. For multi-Document Jobs, they are supplied in each Send-
Document or Send-URI request.
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+----------------------------+----------------------+----------------+
| Attribute | Syntax | MANDATORY? |
+----------------------------+----------------------+----------------+
| document-name | name | MANDATORY |
+----------------------------+----------------------+----------------+
| document-format | type 2 enum | |
+----------------------------+----------------------+----------------+
| document-uri | uri | |
+----------------------------+----------------------+----------------+
4.4.1 document-name (name)
This attribute contains the name of the document used by the client to
initially identify the document. When a client prints by reference,
i.e. includes the document-URI attribute and no document content, this
attribute SHALL be absent.
4.4.2 document-format (type2 enum)
See section 4.2.13 that describes the "document-format" Job Template
attribute. This attribute is a job-template attribute. It may be
specified with the job or separately for each document. In a Print-Job
or Print-URI operation, there is no distinction between job and
document attributes because there is only one job. If document-format
is included with a Create-Job operation, it specifies the format for
all documents. If document-format is included with a Send-Document or
Send-URI operation, it overrides whatever format was specified with
Create-Job.
4.4.3 document-uri (uri)
This attribute contains the URI of the document when the document
content is not included in the Send Document operation. Note: For
Print-URI and Send-URI "document-uri" is an explicit parameter which
sets the "document-uri" attribute in the Document object.
4.5 Printer Description Attributes
These attributes form the attribute group called "printer-
description". A Printer object may be realized in either a print
server or output device. Note: How these attributes are set by an
Administrator is outside the scope of this specification. The
following table summarizes these attributes, their syntax, and whether
or not they are MANDATORY. If they are not MANDATORY, they are
OPTIONAL.
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+----------------------------+----------------------+----------------+
| Attribute | Syntax | MANDATORY? |
+----------------------------+----------------------+----------------+
| printer-uri | uri | MANDATORY |
+----------------------------+----------------------+----------------+
| printer-uri-user | uri | |
+----------------------------+----------------------+----------------+
| printer-name | name | MANDATORY |
+----------------------------+----------------------+----------------+
| printer-location | text | |
+----------------------------+----------------------+----------------+
| printer-description | text | |
+----------------------------+----------------------+----------------+
| printer-more-info-site | uri | |
+----------------------------+----------------------+----------------+
| printer-driver-installer | uri | |
+----------------------------+----------------------+----------------+
| printer-make-and-model | text | |
+----------------------------+----------------------+----------------+
| printer-more-info- | uri | |
| manufacturer | | |
+----------------------------+----------------------+----------------+
| printer-state | type1 enum | MANDATORY |
+----------------------------+----------------------+----------------+
| printer-state-reasons | 1setOf type2 keyword | |
+----------------------------+----------------------+----------------+
| printer-state-message | text | |
+----------------------------+----------------------+----------------+
| printer-is-accepting-jobs | boolean | MANDATORY |
+----------------------------+----------------------+----------------+
| queued-job-count | integer | |
+----------------------------+----------------------+----------------+
| printer-message-from- | text | |
| operator | | |
+----------------------------+----------------------+----------------+
| printer-language | human-language | MANDATORY |
+----------------------------+----------------------+----------------+
| printer-language-supported | 1setOf human-language| MANDATORY |
+----------------------------+----------------------+----------------+
| content-char-set-supported | 1setOf char-set | |
+----------------------------+----------------------+----------------+
| content-char-set | char-set | |
+----------------------------+----------------------+----------------+
| color-supported | boolean | |
+----------------------------+----------------------+----------------+
| message-protection- | keyword | |
| supported | | |
+----------------------------+----------------------+----------------+
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| authentication-author | keyword | |
| ization-supported | | |
+----------------------------+----------------------+----------------+
| color-supported | boolean | |
+----------------------------+----------------------+----------------+
| pdl-override-supported | type2 keyword | |
+----------------------------+----------------------+----------------+
4.5.1 printer-uri (uri)
This attribute contains the URI for the printer. An administrator
determines a printer's URI and sets this attribute to that URI. The
precise format of a printer URI is implementation dependent.
4.5.2 printer-uri-user (uri)
This attribute contains the URI for an HTML page with more information
about this printer.
ISSUE: Get rid of "printer-uri-user" or "printer-more-info-site"?
4.5.3 printer-name (name)
This attribute contains the name of the printer. It is a name that is
more user friendly than the printer-URI. An administrator determines a
printer's name and sets this attribute to that name. This name may be
the last part of the printer's URI or it may be unrelated. In non-US-
English locales, a name may contain characters that are not allowed in
a URI.
4.5.4 printer-location (text)
This attribute identifies the location of this printer. This could
include things like: _in Room 123A, second floor of building XYZ_.
4.5.5 printer-description (text)
This attribute identifies the descriptive information about this
Printer. This could include things like: "This printer can be used
for printing color transparencies for HR presentations", or "Out of
courtesy for others, please print only small (1-5 page) jobs at this
printer", or even "This printer is going away on July 1, 1997, please
find a new printer".
4.5.6 printer-more-info-site (uri)
This attribute contains a URI used to obtain more information about
this specific printer. The information obtained from this URI is
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intended for end user consumption. Features outside the scope of IPP
can be accessed from this URI. The information is intended to be
specific to this printer instance and site services (e.g. job pricing,
services offered, end user assistance). The printer manufacturer may
initially populate this attribute.
4.5.7 printer-driver-installer (uri)
This attribute contains a URI to use to locate the driver installer
for this printer. This attribute is intended for consumption by
automata. The mechanics of print driver installation is outside the
scope of IPP. The printer manufacturer may initially populate this
attribute.
4.5.8 printer-make-and-model (text)
This attribute identifies the make and model of the printer.
4.5.9 printer-more-info-manufacturer (uri)
This attribute contains a URI used to obtain more information about
this type of printer. The information obtained from this URI is
intended for end user consumption. Features outside the scope of IPP
can be accessed from this URI (e.g., latest firmware, upgrades, print
drivers, optional features available). The information is intended to
be germane to this printer without regard to site specific
modifications or services.
4.5.10 printer-state (type1 enum)
This attribute identifies the current state of the printer. The
"printer-state reasons" attribute augments the "printer-state"
attribute to give more detailed information about the Printer in the
given printer state.
A Printer SHALL keep this attribute set in a timely manner to the
value in the table below which most accurately reflects the state of
the Printer. If the printer has jobs that are requesting notification
of printer-problems or job-problems, then _timely manner_ means
continually.. Otherwise, _timely manner_ means whether the Printer
receives a query for this attribute. A Printer NEED NOT implement all
values if they are not applicable to a given implementation.
The following standard values are defined:
'unknown'(2): The Printer state is not known, or is indeterminate.
A Printer SHALL use this state only if it cannot determine its
actual state.
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'idle'(3): If a Printer receives a job (whose required resources
are ready) while in this state, such a job SHALL transit into the
processing state immediately. If the printer-state-reasons
attribute contains any reasons, they SHALL be reasons that would
not prevent a job from transiting into the processing state
immediately, e.g., toner-low. Note: if a Printer controls more
than one output device, the above definition implies that a
Printer is idle if at least one output device is idle.
'processing'(4): If a Printer receives a job (whose required
resources are ready) while in this state, such a job SHALL
transit into the pending state immediately. Such a job SHALL
transit into the processing state only after jobs ahead of it
complete. If the printer-state-reasons attribute contains any
reasons, they SHALL be reasons that do not prevent the current
job from printing, e.g. toner-low. Note: if a Printer controls
more than one output device, the above definition implies that a
Printer is processing if at least one output device is
processing, and none is idle.
'stopped'(5): If a Printer receives a job (whose required
resources are ready) while in this state, such a job SHALL
transit into the pending state immediately. Such a job SHALL
transit into the processing state only after some human fixes the
problem that stopped the printer and after jobs ahead of it
complete printing. The "printer-state-reasons" attribute SHALL
contain at least one reason, e.g. media-jam, which prevents it
from either processing the current job or transiting a pending
job to the processing state.
Note: if a Printer controls more than one output device, the
above definition implies that a Printer is stopped only if all
output devices are stopped. Also, it is tempting to define
stopped as when a sufficient number of output devices are stopped
and leave it to an implementation to define the sufficient
number. But such a rule complicates the definition of stopped
and processing. For example, with this alternate definition of
stopped, a job can move from idle to processing without human
intervention, even though the Printer is stopped.
4.5.11 printer-state-reasons (1setOf type2 keyword)
This attribute supplies additional detail about the printer's state.
Each MAY have asuffix to indicate its level of severity. The three
levels are: report (least severe), warning, and error (most severe).
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- '-report': This suffix indicates that the reason is a "report".
An implementation may choose to omit some or all reports. Some
reports specify finer granularity about the printer state; others
serve as a precursor to a warning. A report SHALL contain nothing
that could affect the printed output.
- '-warning': This suffix indicates that the reason is a "warning".
An implementation may choose to omit some or all warnings.
Warnings serve as a precursor to an error. A warning SHALL
contain nothing that prevents a job from completing, though in
some cases the output may be of lower quality.
- '-error': This suffix indicates that the reason is an "error". .
An implementation SHALL include all errors. If this attribute
contains one or more errors, printer SHALL be in the stopped
state.
If the implementation does not add any one of the three suffixes, all
parties SHALL assume that the reason is an "error".
If a logical Printer controls more than one output device, each value
of this attribute MAY apply to one or more of the output devices. An
error on one output device that does not stop the logical Printer as a
whole MAY appear as a warning in the Printer's "printer-state-reasons
attribute". The "printer-state" for such a Printer may have a value
of 'stopped' even though there are with no "printer-state-reasons"
values that are "errors".
The following standard values are defined:
'media-needed': A tray has run out of media.
'media-jam': The printer has a media jam.
'paused': Someone has paused the Printer. In this state, a Printer
SHALL not produce printed output, but it SHALL perform other
operations requested by a client. If a Printer had been printing
a job when the Printer was paused, the Printer SHALL resume
printing that job when the Printer is no longer paused and leave
no evidence in the printed output of such a pause.
'shutdown': Someone has removed a Printer from service, and it may
be powered down or physical removed. In this state, a Printer
SHALL not produce printed output, and unless the Printer is
realized by a print server that is still active, the Printer
SHALL perform no other operations requested by a client,
including returning this value. If a Printer had been printing a
job when it was shutdown, the Printer need not resume printing
that job when the Printer is no longer shutdown. If the Printer
resumes printing such a job, it may leave evidence in the printed
output of such a shutdown, e.g. the part printed before the
shutdown may be printed a second time after the shutdown.
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'connecting-to-device': The server has scheduled a job on the
Printer and is in the process of connecting to a shared network
output device (and might not be able to actually start printing
the job for an arbitrarily long time depending on the usage of
the output device by other servers on the network).
'timed-out': The server was able to connect to the output device
(or is always connected), but was unable to get a response from
the output device.
'stopping': The printer will be stopping in a while and will change
its reason to printer-stopped. This reason is a non-critical,
even for a Printer with a single output device. When an output-
device ceases accepting jobs, the Printer will have this state
while the output device completes printing.
'stopped-partly': When a Printer controls more than one output
device, this reason indicates that one or more output devices are
stopped. If the reason is a report, fewer than half of the output
devices are stopped. If the reason is a warning, fewer than all
of the output devices are stopped.
'toner-low': The Printer is low on toner.
'spool-area-full': The limit of persistent storage allocated for
spooling has been reached.
4.5.12 printer-state-message (text)
This attribute specifies the additional information about the printer
state in human readable text and it is set by the Printer (or the
Administrator by some mechanism outside the scope of IPP).
ISSUE: Do we want to delete the last phrase and imply that this is a
human readable version of printer-state and printer-state-reason and
not something created by an admin? printer-message-from-the-operator
is from an admin.
4.5.13 printer-is-accepting-jobs (boolean)
This attribute determines whether the printer is currently accepting
job. If the value is true, the printer is accepting jobs. If the
value is false, the printer is currently rejecting any jobs submitted
to it.
Note: This value is independent of the printer state and printer-
state-reasons because its value does not affect the current job;
rather it affects future jobs. This attribute may cause the Printer to
reject jobs when the printer-state is idle or it may cause the Printer
to accepts jobs when the printer-state is stopped.
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4.5.14 queued-job-count (integer(0:2**31 - 1))
This attribute contains a count of the number of jobs that are either
pending and/or processing and is set by the Printer.
4.5.15 printer-message-from-operator (text)
This attribute provides a message from an operator, system
administrator or "intelligent" process to indicate to the end user
information or status of the printer, such as why it is unavailable or
when it is expected to be available.
4.5.16 printer-human-language (human-language)
This attribute specifies the current human-language that the Printer
is operating in.
4.5.17 printer-human-language-supported (1setOf human-language)
This attribute specifies the supported human languages that the
Printer operates in.
4.5.18 printer-content-char-set (char-set)
This attribute specifies the current character set encoding that the
Printer is operating in. If this attribute is not supported, the
Printer MUST support UTF-8.
4.5.19 printer-content-char-set-supported (1setOf char-set)
This attribute specifies the supported character set encodings that
the Printer operates in. If this attribute is not supported, the
Printer MUST support UTF-8.
4.5.20 color-supported (boolean)
This attribute identifies whether the Printer is capable of any type
of color printing at all. All document instructions having to do with
color are embedded within the document PDL (none are external IPP
attributes).
4.5.21 pdl-override (type2 keyword)
A client supplies Job Template attributes to affect the rendering,
production and finishing of the documents in the job. Similar types
of instructions may also be contained in the document to be printed,
that is, within the Page Description Language (PDL) of the document
data. If there is a conflict between the value of one of these IPP
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Job Template attributes, and a corresponding instruction in the
document (either implicit or explicit), it is desirable that the value
of the IPP attribute take precedence over the document instruction.
Until companies that supply interpreters for PDLs, such as PostScript
and PCL allow a way for external attributes (such as IPP attributes)
to take precedence over internal job production instructions, a
Printer might not be able to support the semantics that IPP attributes
override (take on a higher precedence) the embedded PDL instructions.
This attribute expresses how a particular Printer implementation
handles these conflicts.
This attribute takes on the following values:
- 'guaranteed': This value indicates that the Printer guarantees
that all IPP attribute values take precedence over embedded PDL
instructions.
- 'attempted': This value indicates that the Printer attempts to
make sure that IPP attribute values take precedence over embedded
PDL instructions, however there is no guarantee.
- 'ignored': This value indicates that the Printer ignores all IPP
Job Template attributes and it makes no attempts to ensure that
IPP attribute values take precedence over embedded PDL
instructions.
This is a MANDATORY attribute.
Note: Since 'attempted' does not offer any type of guarantee, a given
implementation might not do a very "good" job of attempting to ensure
that IPP attributes take a higher precedence over PDL instructions
embedded in the document data, but it would still be a conforming
implementation.
If the value of this attribute is 'guaranteed', the implementation
MUST guarantee that the IPP attribute values take precedence over any
related job processing instructions in the PDL Job's document data.
This can be done by modifying the interpreter within the output device
itself to understand IPP attributes, or by merging theses Job Template
attributes directly into the document data, or in any other
implementation specific manner. In any case, the semantics of
'guaranteed' MUST be preserved.
4.5.22 Security Related Attributes
The security document [22] describes four common usage scenarios:
- no security
- message protection
- client authentication and authorization
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- mutual authentication, authorization, and message protection
In order to let an end user know what to expect in terms of security,
there are two attributes described below. Since by definition an end
user, because of security reasons, might not be allowed to query these
two attributes, therefore, it is important that if these two
attributes are supported, then they are also populated in the
directory entry (see [24]).
These attributes allow for minimal client/server negotiation regarding
security features. If the Printer requires the feature, the client
can decide whether or not to participate. If the client does not
support the feature, and the Printer requires it, then the client
knows before hand that such an interaction would fail.
Standard values for these two attributes include:
'supported' - means that the Printer is capable of supporting the
security feature (somehow), but it is does not require the client
to use it.
'required' - means that the Printer is capable of supporting the
security feature (somehow) and the client is required to use it.
'none' - means that the Printer is not capable of supporting
message protection at all.
Note: This is a single-valued attribute, not a multi-valued
attribute, i.e., an implementation can not support 'none' and
'required' or any other combination of values.
4.5.22.1 message-protection-supported (keyword)
This attribute is used to determine whether or not a printer supports
or requires message protection (whether it be through encryption or
some other privacy mechanism).
4.5.22.2 authentication-authorization-supported (keyword)
This attribute is used to determine whether or not a printer supports
or requires authentication and authorization.
4.5.23 best-effort (1setOf boolean)
This attribute determines how a Printer handles a conflict between
what a client requests in a create request and what a Printer
supports. The value 'true' means that a best effort attempt to print
the Job is possible. In order to achieve this, the Printer might
ignore some attributes or might have to substitute some supported
value for a requested value which is unsupported. The value 'false'
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means that only total fidelity is supported; a best effort attempt to
print the Job is not possible. In other words, the job can only be
printed exactly as specified in the create request. If one or more of
the client-supplied values in the create request is not supported by
the Printer, the Printer rejects the create request.
For example, if a client supplies a "finishings" Job Template
attribute set to 'staple' but the printer does not support stapling
(not a feature or it is temporarily out of staples) and if the "best-
effort" input parameter is set to 'true' and the Printer's "best-
effort-supported" attributes includes 'true' then the Printer tries to
still print the job even if it can not be stapled.
Note: that the "best-effort" attribute in a create request is unlikely
to be used much. Many clients will submit a job with no attributes,
and the Printer will use default values. Other clients will submit a
job via a GUI that limits the attribute values to values which are
supported. Best effort printing is useful in the GUI context only if
a user expects the job to be moved to another printer and prefers a
sub-optimal result to nothing at all. Best effort printing is most
useful in the case where an end-user uses a command line interface to
request attributes that might not be supported.
5. Conformance
This section describes conformance issues and requirements. This
document introduces model entities such as objects, operations,
attributes, and attribute values. These conformance sections describe
the conformance requirements which apply to these model entities.
5.1 Conditionally Mandatory
For example, a conditionally mandatory attribute means that a Printer
implementation need not support the attribute if the attribute
controls a feature that the output device does not implement or
expose. For example, for an output device that can only print on one
side, a Printer need not support the "sides" attribute. For an output
device that does not support any of the finishing attribute values, a
Printer need not support the "finishing" attribute.
ISSUE: We still have a problem with conditionally mandatory. What
MUST be supported? What NEED NOT? What SHOULD NOT?
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5.2 Client Conformance Requirements
A conforming client SHALL send operations that conform to the protocol
defined in _Internet Printing Protocol/1.0: Protocol Specification_
[23]. For each parameter or attribute included in an operation
request, a conforming client SHALL send a value whose type and value
syntax conforms to the requirement of this document
Otherwise, there are no conformance requirements placed on the user
interfaces provided by IPP clients or their applications. For
example, one application might not allow an end user to submit
multiple documents per job, while another does. One application might
first query a Printer object in order to supply a graphical user
interface (GUI) dialogue box with supported and default values whereas
a different implementation might not.
When sending a Get-Attributes or create request, an IPP client need
not supply any attributes.
A client SHALL be able to accept any of the attribute syntaxes defined
in Section 4.1 that may be returned to it in a response from a Printer
A query response may contain parameters, attributes, and values that
the client does not expect. Therefore, a client implementation MUST
gracefully handle such responses and not refuse to interoperate with a
conforming Printer that is returning extended registered or private
attributes and/or attribute values that conform to Section 6. Clients
may choose to ignore any parametes, attributes, or values that it does
not understand.
5.3 Printer Object Conformance Requirements
This section specifies the conformance requirements for conforming
Printer object implementations with respect to objects, operations,
and attributes.
5.3.1 Objects
Conforming Printer implementations SHALL implement all of the model
objects as defined in this specification in the indicated sections:
Section 0
Printer Object
Section 2.2 Job Object
Section 2.3 Document Object
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5.3.2 Operations
Conforming Printer implementations SHALL implement all of the
MANDATORY model operations, including mandatory responses, as defined
in this specification in the indicated sections:
For a Printer object:
Get-Operations (section 3.2.1) MANDATORY
Print-Job (section 3.2.2) MANDATORY
Print-URI (section 3.2.3) OPTIONAL
Validate-Job (section 3.2.4) MANDATORY
Create-Job (section 3.2.5) OPTIONAL
Get-Jobs (section 3.2.7) MANDATORY
Get-Attributes (section3.2.6) MANDATORY
For a Job object:
Send-Document (section 3.3.1) OPTIONAL
Send-URI (section 3.3.2) OPTIONAL
Cancel-Job (section 3.3.3) MANDATORY
Get-Attributes (section 3.3.4) MANDATORY
Conforming Printer implementations SHALL support all request and
response parameters and all values of such parameters, except for
parameters which are collections of attributes. The following section
on attributes specifies the support required for attributes.
5.3.3 Attributes
Conforming Printer implementations SHALL support all of the MANDATORY
attributes, as defined in this specification in the indicated
sections.
Conforming Printer implementations SHALL support all CONDITIONALLY
MANDATORY attributes as defined in this specification (in the
indicated sections) if in the implementation the condition us true.
If a Printer implements a "xxx-supported" attribute it MUST implement
the corresponding "xxx" default value attribute and vice versa.
ISSUE: For each attribute Job-Template attribute _xxx_, there are 3
attributes: Job attributes _xxx_, Printer attribute _xxx_ (default
value) and Printer attribute _xxx-supported_; a Printer supports
either all three of these attributes or none of the three
If a Printer implements an attribute, it SHALL support only those
values specified in this document or through the extension mechanism
described in the next section. It MAY support any non-empty subset of
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these values. That is, it SHALL support at least one of the specified
values and at most all of them.
5.3.4 Printer extensions
A conforming Printer may support registered extensions and private
extensions, as long as they meet the requirements specified in Section
6.
A conforming Printer SHALL send responses that conform to the protocol
defined in _Internet Printing Protocol/1.0: Protocol Specification_
[23]. For each parameter or attribute included in an operation
response, a conforming printer SHALL send a value whose type and value
syntax conforms to the requirement of this document
5.3.5 Attribute Syntaxes
A Printer SHALL be able to accept any of the attribute syntaxes
defined in Section 4.1 in any operation in which a client may supply
attributes or parameters. Furthermore, a Printer SHALL return
attributes to the client in operation responses that conform to the
syntax specified in Section 4.1.
5.4 Security Conformance Requirements
The security mechanisms being considered for IPP fall outside the
scope of the application layer protocol itself. There are two
mechanisms used to begin secure communications using IPP:
1. Information in the directory entry for an IPP Printer (or from
additional information at a Web site hosting the IPP Printer)
indicate which, if any, security protocols are used in
conjunction with IPP.
2. The URI for the IPP Printer contains the security protocol
information (https://..., etc.).
In either case, the security protocol (if any) is initiated first
which allows for the negotiation of security features. IPP is then
run as an application protocol on top of the security protocols. One
cannot "bootstrap" the security features from IPP itself.
ISSUE: The above is not quite correct. Waiting for better description
from the security document [22].
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6. IANA Considerations (registered and private extensions)
During the development of this standard, the IPP working group
(working with IANA) will register additional keywords and enums while
the standard is in the proposed and draft states according to the
procedures described in this section. IANA will handle registration
of additional enums after this standard is approved in cooperation
with an IANA-appointed registration editor from the IPP working group
according to the procedures described in this section.
6.1 Typed Extensions
This document identifies both keywords and enum values. For private
(unregistered) keyword extensions, implementers SHOULD use keywords
with a suitable distinguishing prefix, such as "xxx-" where xxx is the
(lowercase) company name registered with IANA for use in domain names.
For private (unregistered) enum extension, implementers SHOULD support
values in the reserved integer range (see "enum").
The definitions of these various types are as follows.
6.1.1 Type1
The IPP standard must be revised to add a new keyword or a new enum.
No private keywords or enums are allowed.
This draft contains the following type1 keywords:
- <fill in>
This draft contains the following type1 enums:
- <fill in>
6.1.2 Type2
Implementers can, at any time, add new keyword or enum values by
proposing them to the IPP working group for registration (or an IANA-
appointed registry advisor after the IPP working group is no longer
certified) where they are reviewed for approval. IANA keeps the
registry.
This draft contains the following type2 keywords:
- <fill in>
This draft contains the following type2 enums:
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- <fill in>
6.1.3 Type3
Implementers can, at any time, add new keyword and enum values by
submitting a registration request directly to IANA, no IPP working
group or IANA-appointed registry advisor review is required.
This draft contains the following type3 keywords:
- <fill in>
This draft contains the following type3 enums:
- <fill in>
6.1.4 Type4
Anyone (system administrators, system integrators, site managers,
etc.) can, at any time, add new installation-defined values (keywords
or new enum values) to a local system. Care SHOULD be taken by the
implementers to see that keywords do not conflict with other keywords
defined by the standard or as defined by the implementing product.
There is no registration or approval procedure for type4 values.
This draft contains the following type4 keywords:
- <fill in>
This draft contains the following type4 enums:
- <fill in>
6.2 Registration of MIME types/sub-types for document-formats
The "document-format" attribute IANA enums for indicating document
formats which IANA registers as ? names.
ISSUE: MIME type/sub-types has raised its head again.
7. Security Considerations
There is another Internet-Draft called "Internet Printing
Protocol/1.0: Security" [22]. That document is being drafted and
reviewed in parallel with this document. The mapping of IPP on top of
appropriate security protocols will be described in that document.
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IPP does not introduce any new, general purpose security mechanisms
for authentication and encryption.
A Printer may choose, for security reasons, not to return all
attributes that a client requests. It may even return none of the
requested attributes. In such cases, the status returned is the same
as if the Printer had returned all requested attributes. The client
cannot tell by such a response whether the requested attribute was
present or absent on the Printer.
8. References
[1] Smith, R., Wright, F., Hastings, T., Zilles, S., and Gyllenskog,
J., "Printer MIB", RFC 1759, March 1995.
[2] R Fielding, et al, _Hypertext Transfer Protocol _ HTTP/1.1_ RFC
2068, January 1997
[3] Crocker, D., "Standard for the Format of ARPA Internet Text
Messages", RFC 822, August 1982.
[4] Postel, J., "Instructions to RFC Authors", RFC 1543, October
1993.
[5] ISO/IEC 10175 Document Printing Application (DPA), June 1996.
[6] Herriot, R. (editor), X/Open A Printing System Interoperability
Specification (PSIS), August 1995.
[7] Kirk, M. (editor), POSIX System Administration - Part 4: Printing
Interfaces, POSIX 1387.4 D8, 1994.
[8] Borenstein, N., and Freed, N., "MIME (Multi-purpose Internet Mail
Extensions) Part One: Mechanism for Specifying and Describing the
Format of Internet Message Bodies", RFC 1521, September, 1993.
[9] Braden, S., "Requirements for Internet Hosts - Application and
Support", RFC 1123, October, 1989,
[10] McLaughlin, L. III, (editor), "Line Printer Daemon Protocol" RFC
1179, August 1990.
[11] Berners-Lee, T., Masinter, L., McCahill, M. , "Uniform Resource
Locators (URL)", RFC 1738, December, 1994.
[20] Internet Printing Protocol: Requirements
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[21] Internet Printing Protocol/1.0: Model and Semantics (This
document)
[22] Internet Printing Protocol/1.0: Security
[23] Internet Printing Protocol/1.0: Protocol Specification
[24] Internet Printing Protocol/1.0: Directory Schema
[25] S. Bradner, "Key words for use in RFCs to Indicate Requirement
Levels", RFC 2119 , March 1997
[26] H. Alvestrand, " Tags for the Identification of Languages", RFC
1766, March 1995.
[27] T. Hastings, "Job Monitoring MIB", <draft-ietf-print-mib-
monitoring-01.txt>, June 1997.
[28] F. Yergeau, "UTF-8, a transformation format of Unicode and ISO
10646, RFC 2044, October 1996.
[29] Turner, R. "Printer MIB", draft-ietf-printmib-mib-info-02.txt,
July 8, 1997. This I-D is an update to RFC 1759, March 1995 [1].
[30] P. Mockapetris, "DOMAIN NAMES - IMPLEMENTATION AND
SPECIFICATION", RFC 1035, November 1987.
[31] ?, " ", RFC 2130, ?.
[32] ?, " ", RFC 1514, ?.
[33] ?, " ", RFC 1903, ?.
9. Author's Address
Scott A. Isaacson (Editor)
Novell, Inc.
122 E 1700 S
Provo, UT 84606
Phone: 801-861-7366
Fax: 801-861-4025
EMail: scott_isaacson@novell.com
Tom Hastings
Xerox Corporation
701 S. Aviation Blvd.
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El Segundo, CA 90245
Phone: 310-333-6413
Fax: 310-333-5514
EMail: hastings@cp10.es.xerox.com
Robert Herriot
Sun Microsystems Inc.
901 San Antonio.Road, MPK-17
Palo Alto, CA 94303
Phone: 415-786-8995 (Area code change to 650 in August 1997)
Fax: 415-786-7077 (Area code change to 650 in August 1997)
Email: robert.herriot@eng.sun.com
Roger deBry
HUC/003G
IBM Corporation
P.O. Box 1900
Boulder, CO 80301-9191
Phone: (303) 924-4080
Fax: (303) 924-9889
Email: debry@vnet.ibm.com
Patrick Powell
San Diego State University
9475 Chesapeake Dr., Suite D
San Diego, CA 95123
Phone: (619) 874-6543
Fax: (619) 279-8424
Email: papowell@sdsu.edu
IPP Mailing List: ipp@pwg.org
IPP Mailing List Subscription: ipp-request@pwg.org
IPP Web Page: http://www.pwg.org/ipp/
Other Participants:
Chuck Adams - Tektronix
Jeff Barnett - IBM
Ron Bergman - Data Products
Sylvan Butler, HP
Keith Carter, IBM Corporation
Jeff Copeland - QMS
Andy Davidson - Tektronix
Mabry Dozier - QMS
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Lee Farrell - Canon Information Systems
Steve Gebert - IBM
Babek Jahromi, Microsoft
David Kellerman - Northlake Software
Rick Landau - Digital
Harry Lewis - IBM
Pete Loya - HP
Ray Lutz - Cognisys
Mike MacKay, Novell, Inc.
Carl-Uno Manros, Xerox, Corp.
Jay Martin - Underscore
Stan McConnell - Xerox
Paul Moore, Microsoft
Pat Nogay - IBM
Bob Pentecost - HP
Rob Rhoads - Intel
David Roach - Unisys
Stuart Rowley, Kyocera Hiroyuki Sato - Canon
Bob Setterbo - Adobe
Devon Taylor, Novell, Inc.
Mike Timperman - Lexmark
Randy Turner - Sharp
Atsushi Yuki - Kyocera
Lloyd Young - Lexmark
Bill Wagner - DPI
Jim Walker - DAZEL
Chris Wellens - Interworking Labs
Rob Whittle - Novell
Don Wright - Lexmark
Peter Zehler, Xerox, Corp.
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10. APPENDIX A: Terminology
This specification uses the terminology defined in this section.
10.1 Conformance Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [25]. The
sections below reiterate these definitions and include some additional
ones.
10.1.1 MUST
This word, or the terms "REQUIRED", "SHALL" or "MANDATORY", means
that the definition is an absolute requirement of the specification.
10.1.2 MUST NOT
This phrase, or the phrase "SHALL NOT", means that the definition is
an absolute prohibition of the specification.
10.1.3 SHOULD
This word, or the adjective "RECOMMENDED", means that there may exist
valid reasons in particular circumstances to ignore a particular item,
but the full implications must be understood and carefully weighed
before choosing a different course.
10.1.4 SHOULD NOT
This phrase, or the phrase "NOT RECOMMENDED" means that there may
exist valid reasons in particular circumstances when the particular
behavior is acceptable or even useful, but the full implications
should be understood and the case carefully weighed before
implementing any behavior described with this label.
10.1.5 MAY
This word, or the adjective "OPTIONAL", means that an item is truly
optional. One vendor may choose to include the item because a
particular marketplace requires it or because the vendor feels that it
enhances the product while another vendor may omit the same item. An
implementation which does not include a particular option MUST be
prepared to interoperate with another implementation which does
include the option, though perhaps with reduced functionality. In the
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same vein an implementation which does include a particular option
MUST be prepared to interoperate with another implementation which
does not include the option (except, of course, for the feature the
option provides.)
10.1.6 CONDITIONALLY MANDATORY
This term means that an item MUST be implemented in a conforming
implementation if the specified condition is true. Conversely, a
conforming implementation NEED NOT implement the item if the specified
condition is false.
ISSUE: Bob H. writes: After writing the paragraphs below, I have
concluded that job-template attributes should all be optional, and we
should drop the "conditionally mandatory" term. At the very least,
they have to be optional for print servers. There may be some
argument for making some of them conditionally mandatory in embedded
printers, but the extra complexity of the explanation may not be worth
the trouble. We all need to give this issue some more thought. As long
as the explanation is so murky, I don't think any two people would
come up with the same list of mandatory attributes for an
implementation and that is no better than making them optional.
Now for the details.
Before discussing the issue, we should understand that there are two
categories of attributes:
o printer control (e.g. media or sides)
o job control (e.g. job-priority, job-sheets or notify-events)
And there are two types of implementations
o embedded printer
o print server
We also need to look at the model document's definition of
conditionally mandatory. The following is paraphrasing from 3 parts of
the model document. It says an implementation must support the
attribute if it knows about and is able to support it, and need not
support the attribute that controls a feature that the output device
does not implement or expose. It also says that if a certain
implementation supports only one well-known value of some "xxx-
supported" attribute, it is not required that that implementation
support that attribute.
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This definition is somewhat reasonable for an embedded printer. It is
easy to determine if an output device supports an IPP printer control
attribute, though if the feature has only one value it may not be easy
to determine if the value is "well-known". If a printer supports only
letter paper, then the rules above say that support of "media" is not
required. But suppose the size is B only. Is B "well-known" enough to
qualify for the exclusion? If IPP has an exclusion for a known
feature, the rule should exclude "non- selectable" features rather
than "well-known" because "well-known" is subjective.
This definition is somewhat more difficult for job control attributes
in an embedded printer. There is no hardware associated with job-
sheets or job-priority. So an output-device "knows" about such a
feature only if its software implements it, in which case IPP likely
supports it. This all seems rather circular. So the answer is that all
job control attributes are optional for embedded printers.
For print servers, the rule is quite inscrutable because a print
server can potentially serve all types of printers with a variety of
features. Are all printer-control attributes mandatory because a
connected printer could have the feature or all printer-control
attributes optional because the printer-server itself has none of the
features? Because job-control attributes are normally implemented by a
print servers and not output devices, the feature doesn't exist unless
it is implemented, hence nothing is mandatory. So I am left not
knowing what to do for a print server. Can I implement nothing or must
I implement all to be conforming. I think everything is optional.
When I look at the four combinations of the 2 types of implementations
and 2 types of attributes, I conclude that only printer control
attributes in embedded printer implementations could be conditionally
mandatory. All job control attributes in embedded printers and all
attributes in print servers must be optional.
10.1.7 NEED NOT
The verb "NEED NOT" indicates an action that the subject of the
sentence does not have to implement in order to claim conformance to
the standard. The verb "NEED NOT" is used instead of "MAY NOT" since
"MAY NOT" sounds like a prohibition.
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10.2 Model Terminology
10.2.1 Keyword
Keywords are used within this document as identifiers of semantic
entities within the abstract model. Attribute names, some attribute
values, attribute syntaxes, and attribute group names are represented
as keywords. In this document, a keyword is a sequence of characters
(length of 1 to 255) which consists of the following ASCII characters:
lower-case letters ("a" - "z"), digits ("0" - "9"), hyphen ("-"),
period ("."), and underscore ("_"). A keyword starts with a lower-
case letter.
10.2.2 Parameters
A parameter is an item of information supplied in an operation
consisting of a parameter name and a parameter value(s). Each
parameter has a specific syntax. Clients supply input parameters in
operation requests and servers return output parameters in operation
responses. Some parameters have corresponding object attributes; some
do not. All parameters are defined in section 3.
10.2.2.1 Parameter Name
Each parameter is uniquely identified in this document by its
parameter name which is a keyword. The keyword parameter name is
given in the section header describing that parameter. In running
text in this document, parameter names are indicated inside double
quotation marks (").
10.2.2.2 Parameter Value
Each parameter has one or more values. Parameter values are
represented in the syntax type specified for that parameter. In
running text in this document, parameter values are indicated inside
single quotation marks ('), whether their parameter syntax is keyword,
integer, text, etc.
10.2.2.3 Parameter Syntax
Each parameter is defined using an explicit syntax. In this document,
each syntax type is defined as a keyword with specific meaning. The
protocol specification document [23] indicates the actual on-the-wire
encoding for each parameter syntax. Parameter syntaxes are the same as
attribute syntaxes and they are defined in section 4.1.
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10.2.3 Attributes
An attribute is an item of information that is associated with an
instance of an IPP object. An attribute consists of an attribute name
and an attribute value(s). Each attribute has a specific syntax..
All attributes are defined in section 4.
An interesting set of attributes is called Job Template Attributes
(these attributes are described in detail in section 4.2.) The client
optionally supplies Job Template attributes as input parameters in a
create request (operation requests that create Job objects). The
Printer object has associated attributes which define supported and
default values for the Printer. Thee following rules apply:
- When a Job Template attribute is supplied as an input parameter
in a create request, the attribute and its value describe the
desired job processing behavior.
- The Printer object's supported attribute describes what behaviors
are possible.
- The Printer object's default value attribute describes what will
be done when no other job processing information is supplied by
the client.
10.2.3.1 Attribute Name
Each attribute is uniquely identified in this document by its
attribute name which is a keyword. The keyword attribute name is
given in the section header describing that attribute. In running
text in this document, attribute names are indicated inside double
quotation marks (").
10.2.3.2 Attribute Group Name
Related attributes are grouped into named groups. The name of the
group is a keyword. The group name may be used in an input parameter
in place of naming all the attributes in the group explicitly.
Attribute groups are defined in section 4.
10.2.3.3 Attribute Value
Each attribute has one or more values. Attribute values are
represented in the syntax type specified for that attribute. In
running text in this document, attribute values are indicated inside
single quotation marks ('), whether their attribute syntax is keyword,
integer, text, etc.
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10.2.3.4 Attribute Syntax
Each attribute is defined using an explicit attribute syntax. In this
document, each attribute syntax is defined as a keyword with specific
meaning. The protocol specification document [23] indicates the
actual on-the-wire encoding for each attribute syntax. Attribute
syntaxes are defined in section 4.1.
10.2.4 Supports
By definition, an implementation (an instance of an IPP object)
supports an attribute (or a particular value of an attribute) only if
that implementation responds with the corresponding attribute and
value in a response to a query for that attribute. A given
implementation may exhibit a behavior that corresponds to the value of
some attribute, but if the implementation, when queried for that
attribute, doesn't respond with the supported attribute populated with
that specific value, then as far as IPP is concerned, that
implementation does not support that feature.
A conforming implementation SHALL support all MANDATORY attributes and
all CONDITIONALLY MANDATORY attributes where the implementation
satisfies the condition associated with the CONDITIONALLY MANDATORY
attribute. Conformance to IPP does not mandate that all
implementations support all possible values representing all possible
job processing behaviors and features. For example, if a given
instance of a Printer supports only certain document formats, then
that Printer responds with the "document-format-supported" attribute
populated with a set of values, possibly only one, taken from the
entire set of possible values defined in this model document. This
set of values represent the Printer's set of supported document
formats. Another example is the "finishings-supported" attribute. If
a Printer is not physically capable of stapling (there is no stapler
in the output device itself), the "finishings-supported" attribute
MUST NOT be populated with the value of 'staple'.
ISSUE: We have said that conformance does not mandate support for any
values. For example, a printer could have a stapler and supported
finishings-supported but not the value _staple_ and still be in
conformance, though not useful. Is this true?
In order to ease the implementation burden, if a certain
implementation supports only one well-known value of some "xxx-
supported" attribute, it is NOT REQUIRED that that implementation
support that attribute. For example, if a Printer object represents a
physical device that can not print on two sides of the media, the only
possible value for the "sides-supported" attribute could be 'one-
sided'. In this case, it is NOT REQUIRED that the implementation
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support the "sides-supported" attribute since a client could infer
that the implementation supports only single-sided printing from the
absence of the "sides-supported" attribute. If for some reason, an
implementation only supported "two-sided-long-edge" then that
implementation MUST support the "sides-supported" attribute to be a
conforming implementation. The "well known value" for CONDITIONALLY
MANDATORY attribute is specified in the section describing that
attribute.
ISSUE: The "well known value" condition for each Job Template
attribute has not yet been identified. The most difficult one will be
"media-supported", that is there probably not one "well known value"
for "media supported". This "well known value" is a very slippery
slope...
Note: The supported attributes are set (populated) by some
administrative process or automatic sensing mechanism that is outside
the scope of IPP.
11. APPENDIX B: Status Codes
This section defines status code keywords that are used to provide
semantic information on the results of an operation request. Each
operation response MUST include a status code. For error type status
codes, the response MAY also contain a status message that provides a
short textual description of the status. The status code is intended
for use by automata, and the status message is intended for the human
end user. Since the status message is an OPTIONAL component of the
operation response, an IPP application (i.e. a browser, GUI, print
driver or gateway) is NOT REQUIRED to examine or display the status
message.
The prefix of the status keyword defines the class of response as
follows:
"informational" - Request received, continuing process
"successful" - The action was successfully received, understood,
and accepted
"redirection" - Further action must be taken in order to complete
the request
"client-error" - The request contains bad syntax or cannot be
fulfilled
"server-error" - The server failed to fulfill an apparently valid
request
IPP status codes are extensible. IPP applications are NOT REQUIRED to
understand the meaning of all registered status codes, though such
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understanding is obviously desirable. However, applications SHALL
understand the class of any status code, as indicated by the prefix,
and treat any unrecognized response as being equivalent to the first
status code of that class, with the exception that an unrecognized
response shall not be cached. For example, if an unrecognized status
code of "client-error-foo-bar" is received by the client, it can
safely assume that there was something wrong with its request and
treat the response as if it had received a "client-error-bad-request"
status code. In such cases, IPP applications could present the
OPTIONAL message (if present) to the end user since the message is
likely to contain human readable information which will help to
explain the unusual status.
11.1 Status Codes (type2 keyword)
Each status code is described below. Section 11.2 contains a table
that indicates which status codes apply to which operations.
11.1.1 Informational
This class of status code indicates a provisional response and is to
be used for informational purposes only.
There are no status codes defined in IPP 1.0 for this class of status
code.
11.1.2 Successful Status Codes
This class of status code indicates that the client's request was
successfully received, understood, and accepted.
11.1.2.1 successful-ok
The request has succeeded.
11.1.2.2 successful-ok-ignored-or-substituted-attributes
The request has succeeded, but since "best effort" printing was
allowed and requested, in order to print the job, some attributes were
ignored or unsupported values were substituted with supported values.
11.1.3 Redirection Status Codes
This class of status code indicates that further action needs to be
taken to fulfill the request.
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There are no status codes defined in IPP 1.0 for this class of status
code.
11.1.4 Client Error Status Codes
This class of status code is intended for cases in which the client
seems to have erred. The server SHOULD return a message containing an
explanation of the error situation and whether it is a temporary or
permanent condition.
11.1.4.1 client-error-bad-request
The request could not be understood by the server due to malformed
syntax. The IPP application SHOULD NOT repeat the request without
modifications.
11.1.4.2 client-error-forbidden
The server understood the request, but is refusing to fulfill it.
Additional authentication information or authorization credentials
will not help and the request SHOULD NOT be repeated. This status
code is commonly used when the server does not wish to reveal exactly
why the request has been refused or when no other response is
applicable.
11.1.4.3 client-error-not-authenticated
The request requires user authentication. The IPP client may repeat
the request with suitable authentication information. If the request
already included authentication information, then this status code
indicates that authorization has been refused for those credentials.
If this response contains the same challenge as the prior response,
and the user agent has already attempted authentication at least once,
then the response message may contain relevant diagnostic information.
This status codes reveals more information than "client-error-
forbidden".
11.1.4.4 client-error-not-authorized
The requester is not authorized to perform the request. Additional
authentication information or authorization credentials will not help
and the request SHOULD be repeated. This status code is used when the
server wishes to reveal that the authentication information is
understandable, however, the requester is explicitly not authorized to
perform the request. This status codes reveals more information than
"client-error-forbidden".
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11.1.4.5 client-error-not-possible
This status code is used when the request is for something that can
not happen. For example, there might be a request to cancel a job
that has already been aborted by the system. The IPP client SHOULD
NOT repeat the request.
11.1.4.6 client-error-timeout
The client did not produce a request within the time that the server
was prepared to wait. For example, a client issued a Create-Job
operation and then, after a long period of time, issued a Send-
Document operation and this error status code was returned in response
to the Send-Document request. The server might have been forced to
clean up resources that had been held for the waiting additional
Documents. The server was forced to close the Job since the client
took too long. The client SHOULD NOT repeat the request without
modifications.
11.1.4.7 client-error-not-found
The server has not found anything matching the request URI. No
indication is given of whether the condition is temporary or
permanent. For example, a client with an old reference to a Job (a
URI) tries to cancel the Job, however in the mean time the Job might
have been completed and all record of it at the Printer has been
deleted. This status code, 'client-error-not-found' is returned
indicating that the referenced Job can not be found. This error
status code is also used when a client supplies a URI as a reference
to the document data in either a Print-URI or Send-URI operation
however the document can not be found.
In practice, an IPP application should avoid a not found situation by
first querying and presenting a list of valid Printer URIs and Job
URIs to the end-user.
11.1.4.8 client-error-gone
The requested object is no longer available at the server and no
forwarding address is known. This condition should be considered
permanent. Clients with link editing capabilities should delete
references to the request URI after user approval. If the server does
not know or has no facility to determine, whether or not the condition
is permanent, the status code "client-error-not-found" should be used
instead.
This response is primarily intended to assist the task of web
maintenance by notifying the recipient that the resource is
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intentionally unavailable and that the server owners desire that
remote links to that resource be removed. It is not necessary to mark
all permanently unavailable resources as "gone" or to keep the mark
for any length of time -- that is left to the discretion of the server
owner.
11.1.4.9 client-error-request-entity-too-large
The server is refusing to process a request because the request entity
is larger than the server is willing or able to process. An IPP
Printer returns this status code when it limits the size of print jobs
and it receives a print job that exceeds that limit or when the
operation parameters are so many that their encoding causes the
request entity to exceed server capacity.
11.1.4.10 client-error-request-URI-too-long
The server is refusing to service the request because the request URI
is longer than the server is willing to interpret. This rare
condition is only likely to occur when a client has improperly
submitted a request with long query information (e.g. an IPP
application allows an end-user to enter an invalid URI), when the
client has descended into a URI "black hole" of redirection (e.g., a
redirected URI prefix that points to a suffix of itself), or when the
server is under attack by a client attempting to exploit security
holes present in some servers using fixed-length buffers for reading
or manipulating the Request-URI.
11.1.4.11 client-error-unsupported-document-format
The server is refusing to service the request because the print data
is in a format, as specified in the "document-format" input parameter,
that is not supported by the IPP Printer.
11.1.4.12 client-error-attribute-not-supported
For a Create-Job, Print-Job or Validate-Job operation, if the IPP
Printer does not support one or more attributes or attribute values
supplied in the request, the Printer shall return this status. For
example, if the request requires A4 paper and that paper size is not
supported by the Printer, and "best effort" printing was not
requested, the Printer shall return this status.
For a Get-Jobs operation, if the IPP Printer does not support one of
the requested attributes, the Printer shall return this status.
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In practice, an IPP application should avoid this situation by
querying an IPP Printer for its valid attributes and values before
performing an operation on the Printer.
11.1.5 Server Error Status Codes
This class of status codes indicates cases in which the server is
aware that it has erred or is incapable of performing the request.
The server SHOULD include a message containing an explanation of the
error situation, and whether it is a temporary or permanent condition.
11.1.5.1 server-error-internal- error
The server encountered an unexpected condition that prevented it from
fulfilling the request. This error status code differs from "server-
error-temporary-error" in that it implies a more permanent type of
internal error. It also differs from "server-error-device-error" in
that it implies an unexpected condition (unlike a paper-jam or out-of-
toner problem which is undesirable but expected). This error status
code indicates that probably some knowledgeable human intervention is
required.
11.1.5.2 server-error-operation-not-supported
The server does not support the functionality required to fulfill the
request. This is the appropriate response when the server does not
recognize an operation or is not capable of supporting it.
11.1.5.3 server-error-service-unavailable
The server is currently unable to handle the request due to a
temporary overloading or maintenance of the server. The implication
is that this is a temporary condition which will be alleviated after
some delay. If known, the length of the delay may be indicated in the
message. If no delay is given, the IPP application should handle the
response as it would for a "server-error-temporary-internal-error"
response. If the condition is more permanent, the error status codes
"client-error-gone" or "client-error-not-found" could be used.
11.1.5.4 server-error-version-not-supported
The server does not support, or refuses to support, the IPP protocol
version that was used in the request message. The server is
indicating that it is unable or unwilling to complete the request
using the same version as supplied in the request other than with this
error message. The response should contain a Message describing why
that version is not supported and what other versions are supported by
that server.
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A conforming IPP client shall specify the valid version (IPP 1.0)on
each request. A conforming IPP server (IPP 1.0) SHALL NOT return this
status code to a conforming IPP 1.0 client. An IPP server shall
return this status code to a non-conforming IPP client.
11.1.5.5 server-error-device-error
A printer error, such as a paper jam, occurs while the IPP Printer
processes a Print or Send operation. The response contains the true
Job Status (the values of the "job-state" and "job-state-reasons"
attributes). Additional information can be returned in the optional
"job-state-message" attribute value or in the OPTIONAL status code
message that describes the error in more detail. This error status
code MAY be returned even though the operation was successful (the Job
was submitted and is now in the 'pending' state waiting to be
processed).
ISSUE: This doesn't seem like a good error. If the create request
succeeded, an OK should be returned. The job-status of printer-stopped
gives information about the printer being stopped.
11.1.5.6 server-error-temporary-error
A temporary error such as a buffer full write error, a memory overflow
(i.e. the document data exceeds the memory of the Printer), or a disk
full condition, occurs while the IPP Printer processes an operation.
The client MAY try the unmodified request again at some later point in
time with an expectation that the temporary internal error condition
may have been cleared.
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11.2 Status Keywords for IPP Operations
PJ = Print-Job, PU = Print-URI, CJ = Create-Job, SD = Send-Document
SU = Send-URI, V = Validate-Job, GA = Get-Attributes, GJ = Get-Jobs
GO = Get-Operations, C = Cancel-Job
IPP Operations
IPP Status Keyword PJ PU CJ SD SU V GA GJ GO C
------------------ -- -- -- -- -- - -- -- -- -
successful-OK x x x x x x x x x x
client-error-bad-request x x x x x x x x x x
client-error-not-authenticated x x x x x x x x x x
client-error-not-authorized x x x x x x x x x x
client-error-forbidden x x x x x x x x x x
client-error-not-possible x x x x x x x x x x
client-error-not-found x x x x x x x x x x
client-error-timeout x x x x x x x x x x
client-error-gone x x x x x x x x x x
client-error-request-entity-too-large x X X X X X X X X X
client-error-request-URI-too-long x x x x x x x x x x
client-error-unsupported-document-format x x x x
client-error-attribute-value-not- x x x x
supported
server-error-internal-error x x x x x x x x x x
server-error-service-unavailable x x x x x x x x x x
server-error-timeout x x x x x x x x x x
server-error-HTTP-version-not-supported x x x x x x x x x x
server-error-IPP-version-not-supported x x x x x x x x x x
server-error-device-error x x x x x
server-error-temporary-error x x x x x
ISSUE: The above needs to be re-reviewed in greater detail.
12. APPENDIX C: "document-format" enum values
The Printer Working Group has registered a set of type2 enum values
with IANA as part of the IETF Printer MIB [1] project. The standard
value assigned by the PWG starts with the four letters: "lang", in
order to follow SNMP ASN.1 rules that all enum symbols SHALL start
with a lower case letter. The integer enum value is used as the value
the "document-format" attribute.
This APPENDIX lists the document formats that are currently registered
with IANA. As with all type 2 and type 3 enums, when additional enum
values are registered with IANA, they may be used in IPP withhout
updating this appendix.
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ISSUE: PDF does not have an enum value, though it has a MIME type.
Adobe needs to register PDF as one of the standard values.
The standard values registered at the current time are:
'other': 1 -
'langPCL': 3 - PCL. Starting with PCL version 5, HP-GL/2 is
included as part of the PCL language. PCL and HP-GL/2 are
registered trademarks of Hewlett-Packard Company.
'langHPGL': 4 - Hewlett-Packard Graphics Language. HP-GL is a
registered trademark of Hewlett-Packard Company.
'langPJL': 5 - Peripheral Job Language. Appears in the data stream
between data intended for a page description language. Hewlett-
Packard Co.
'langPS': 6 - PostScript Language (tm) Postscript - a trademark of
Adobe Systems Incorporated which may be registered in certain
jurisdictions
'langIPDS': 7 - Intelligent Printer Data Stream Bi-directional
print data stream for documents consisting of data objects (text,
image, graphics, bar codes), resources (fonts, overlays) and
page, form and finishing instructions. Facilitates system level
device control, document tracking and error recovery throughout
the print process. Pennant Systems, IBM
'langPPDS': 8 - IBM Personal Printer Data Stream. Originally
called IBM ASCII, the name was changed to PPDS when the Laser
Printer was introduced in 1989. Lexmark International, Inc.
'langEscapeP': 9 - Epson Corp.
'langEpson': 10 -
'langDDIF': 11 - Digital Document Interchange Format Digital
Equipment Corp., Maynard MA
'langInterpress': 12 - Xerox Corp.
'langISO6429': 13 - ISO 6429. Control functions for Coded
Character Sets (has ASCII control characters, plus additional
controls for character imaging devices.) ISO Standard, Geneva,
Switzerland
'langLineData': 14 - line-data: Lines of data as separate ASCII or
EBCDIC records and containing no control functions (no CR, LF,
HT, FF, etc.). For use with traditional line printers. May use
CR and/or LF to delimit lines, instead of records. See ISO 10175
Document Printing Application (DPA) ISO standard, Geneva,
Switzerland
'langMODCA': 15 - Mixed Object Document Content Architecture
Definitions that allow the composition, interchange, and
presentation of final form documents as a collection of data
objects (text, image, graphics, bar codes), resources (fonts,
overlays) and page, form and finishing instructions. Pennant
Systems, IBM
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'langREGIS': 16 - Remote Graphics Instruction Set, Digital
Equipment Corp., Maynard MA
'SCS': 17 - SNA Character String Bi-directional print data stream
for SNA LU-1 mode of communications IBM
'langSPDL': 18 - ISO 10180 Standard Page Description Language ISO
Standard
'langTEK4014': 19 - Tektronix Corp.
'langPDS': 20 -
'langIGP': 21 - Printronix Corp.
'langCodeV': 22 - Magnum Code-V, Image and printer control language
used to control impact/dot- matrix printers. QMS, Inc., Mobile
AL
'langDSCDSE': 23 - DSC-DSE: Data Stream Compatible and Emulation
Bi-directional print data stream for non-SNA (DSC) and SNA LU-3
3270 controller (DSE) communications IBM
'langWPS': 24 - Windows Printing System, Resource based
command/data stream used by Microsoft At Work Peripherals.
Developed by the Microsoft Corporation.
'langLN03': 25 - Early DEC-PPL3, Digital Equipment Corp.
'langCCITT': 26 -
'langQUIC': 27 - QUIC (Quality Information Code), Page Description
Language for laser printers. Included graphics, printer control
capability and emulation of other well- known printer . QMS,
Inc.
'langCPAP': 28 - Common Printer Access Protocol Digital Equipment
Corp
'langDecPPL': 29 - Digital ANSI-Compliant Printing Protocol (DEC-
PPL) Digital Equipment Corp
'langSimpleText': 30 - simple-text: character coded data, including
NUL, CR , LF, HT, and FF control characters. See ISO 10175
Document Printing Application (DPA) ISO standard, Geneva,
Switzerlan
'langNPAP': 31 - Network Printer Alliance Protocol (NPAP). This
protocol has been superseded by the IEEE 1284.1 TIPSI standard.
(ref. LangTIPSI(49)).
'langDOC': 32 - Document Option Commands, Appears in the data
stream between data intended for a page description . QMS, Inc
'langimPress': 33 - imPRESS, Page description language originally
developed for the ImageServer line of systems. A binary language
providing representations for text, simple graphics (rules,
lines, conic sections), and some large forms (simple bit-map and
CCITT group 3/4 encoded).The language was intended to be sent
over an 8-bit channel and supported early document preparation
languages (e.g. TeX and TROFF). QMS, Inc.
'langPinwriter': 34 - 24 wire dot matrix printer for USA, Europe,
and Asia except Japan. More widely used in Germany, and some
Asian countries than in US. NEC
'langNPDL': 35 - Page printer for Japanese market. NEC
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'langNEC201PL': 36 - Serial printer language used in the Japanese
market. NEC
'langAutomatic': 37 - Automatic PDL sensing. Automatic sensing of
the interpreter language family by the printer examining the
document content. Which actual interpreter language families are
sensed depends on the printer implementation.
'langPages': 38 - Page printer Advanced Graphic Escape Set IBM
Japan
'langLIPS': 39 - LBP Image Processing System
'langTIFF': 40 - Tagged Image File Format (Aldus)
'langDiagnostic': 41 - A hex dump of the input to the interpreter
'langPSPrinter': 42 - The PostScript Language used for control
(with any PDLs) Adobe Systems Incorporated
'langCaPSL': 43 - Canon Print Systems Language
'langEXCL': 44 - Extended Command Language Talaris Systems Inc
'langLCDS': 45 - Line Conditioned Data Stream Xerox Corporatio
'langXES': 46 - Xerox Escape Sequences Xerox Corporation
'langPCLXL': 47 - Printer Control Language. Extended language
features for printing, and printer control. Technical reference
manual # TBD. Hewlett-Packard Co.
'langART': 48 - Advanced Rendering Tools (ART). Page Description
language originally developed for the Laser Press printers.
Tehnical reference manual: "ART IV Reference Manual", No F33M.
Fuji Xerox Co., Ltd.
'langTIPSI': 49 - Transport Independent Printer System Interface
(ref. IEEE Std. 1284.1)
'langPrescribe': 50 - Page description and printer control
language. It can be described with ordinary ASCII characters.
Technical reference manual: "PRESCRIBE II Programming Manual"
'langLinePrinter': 51 - A simple-text character stream which
supports the control codes LF, VT, FF and CR plus Centronics or
Dataproducts Vertical Format Unit (VFU). language is commonly
used on many older model line and matrix printers.
'langIDP': 52 - Imaging Device Protocol Apple Computer.
'langXJCL': 53 - Xerox Corp.
ISSUE: Add TIFF-F?
One special value is 'langAutomatic (37)'. However a client SHALL NOT
supply the value 'langAutomatic' in a create request. If the
"document-format" is unknown for a certain document, the client SHALL
NOT supply the attribute in the create request or the Send-Document
Request.
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13. APPENDIX D: "media" keyword values
Standard keyword values are taken from several sources.
Standard values are defined (taken from ISO DPA[5] and the Printer
MIB[1]):
'default': The default medium for the output device
'iso-a4-white': Specifies the ISO A4 white medium
'iso-a4-colored': Specifies the ISO A4 coloured medium
'iso-a4-transparent' Specifies the ISO A4 transparent medium
'iso-a3-white': Specifies the ISO A3 white medium
'iso-a3-colored': Specifies the ISO A3 coloured medium
'iso-a5-white': Specifies the ISO A5 white medium
'iso-a5-colored': Specifies the ISO A5 coloured medium
'iso-b4-white': Specifies the ISO B4 white medium
'iso-b4-colored': Specifies the ISO B4 coloured medium
'iso-b5-white': Specifies the ISO B5 white medium
'iso-b5-colored': Specifies the ISO B5 coloured medium
'jis-b4-white': Specifies the JIS B4 white medium
'jis-b4-colored': Specifies the JIS B4 coloured medium
'jis-b5-white': Specifies the JIS B5 white medium
'jis-b5-colored': Specifies the JIS B5 coloured medium
The following standard values are defined for North American media:
'na-letter-white': Specifies the North American letter white medium
'na-letter-colored': Specifies the North American letter coloured
medium
'na-letter-transparent': Specifies the North American letter
transparent medium
'na-legal-white': Specifies the North American legal white medium
'na-legal-colored': Specifies the North American legal coloured
medium
The following standard values are defined for envelopes:
'iso-b4-envelope': Specifies the ISO B4 envelope medium
'iso-b5-envelope': Specifies the ISO B5 envelope medium
'iso-c3-envelope': Specifies the ISO C3 envelope medium
'iso-c4-envelope': Specifies the ISO C4 envelope medium
'iso-c5-envelope': Specifies the ISO C5 envelope medium
'iso-c6-envelope': Specifies the ISO C6 envelope medium
'iso-designated-long-envelope': Specifies the ISO Designated Long
envelope medium
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'na-10x13-envelope': Specifies the North American 10x13 envelope
medium
'na-9x12-envelope': Specifies the North American 9x12 envelope
medium
'monarch-envelope': Specifies the Monarch envelope
'na-number-10-envelope': Specifies the North American number 10
business envelope medium
'na-7x9-envelope': Specifies the North American 7x9 inch envelope
'na-9x11-envelope': Specifies the North American 9x11 inch envelope
'na-10x14-envelope': Specifies the North American 10x14 inch
envelope
'na-number-9-envelope': Specifies the North American number 9
business envelope
'na-6x9-envelope': Specifies the North American 6x9 inch envelope
'na-10x15-envelope': Specifies the North American 10x15 inch
envelope
The following standard values are defined for the less commonly used
media (white-only):
'executive-white': Specifies the white executive medium
'folio-white': Specifies the folio white medium
'invoice-white': Specifies the white invoice medium
'ledger-white': Specifies the white ledger medium
'quarto-white': Specified the white quarto medium
'iso-a0-white': Specifies the ISO A0 white medium
'iso-a1-white': Specifies the ISO A1 white medium
'iso-a2-white': Specifies the ISO A2 white medium
'iso-a6-white': Specifies the ISO A6 white medium
'iso-a7-white': Specifies the ISO A7 white medium
'iso-a8-white': Specifies the ISO A8 white medium
'iso-a9-white': Specifies the ISO A9 white medium
'iso-10-white': Specifies the ISO A10 white medium
'iso-b0-white': Specifies the ISO B0 white medium
'iso-b1-white': Specifies the ISO B1 white medium
'iso-b2-white': Specifies the ISO B2 white medium
'iso-b3-white': Specifies the ISO B3 white medium
'iso-b6-white': Specifies the ISO B6 white medium
'iso-b7-white': Specifies the ISO B7 white medium
'iso-b8-white': Specifies the ISO B8 white medium
'iso-b9-white': Specifies the ISO B9 white medium
'iso-b10-white': Specifies the ISO B10 white medium
'jis-b0-white': Specifies the JIS B0 white medium
'jis-b1-white': Specifies the JIS B1 white medium
'jis-b2-white': Specifies the JIS B2 white medium
'jis-b3-white': Specifies the JIS B3 white medium
'jis-b6-white': Specifies the JIS B6 white medium
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'jis-b7-white': Specifies the JIS B7 white medium
'jis-b8-white': Specifies the JIS B8 white medium
'jis-b9-white': Specifies the JIS B9 white medium
'jis-b10-white': Specifies the JIS B10 white medium
The following standard values are defined for engineering media:
'a': Specifies the engineering A size medium
'b': Specifies the engineering B size medium
'c': Specifies the engineering C size medium
'd': Specifies the engineering D size medium
'e': Specifies the engineering E size medium
The following standard values are defined for input-trays (from ISO
DPA and the Printer MIB):
'top': The top input tray in the printer.
'middle': The middle input tray in the printer.
'bottom': The bottom input tray in the printer.
'envelope': The envelope input tray in the printer.
'manual': The manual feed input tray in the printer.
'large-capacity': The large capacity input tray in the printer.
'main': The main input tray
'side': The side input tray
The following standard values are defined for media sizes (from ISO
DPA):
'iso-a0': Specifies the ISO A0 size: 841 mm by 1189 mm as defined
in ISO 216
'iso-a1': Specifies the ISO A1 size: 594 mm by 841 mm as defined in
ISO 216
'iso-a2': Specifies the ISO A2 size: 420 mm by 594 mm as defined in
ISO 216
'iso-a3': Specifies the ISO A3 size: 297 mm by 420 mm as defined in
ISO 216
'iso-a4': Specifies the ISO A4 size: 210 mm by 297 mm as defined in
ISO 216
'iso-a5': Specifies the ISO A5 size: 148 mm by 210 mm as defined in
ISO 216
'iso-a6': Specifies the ISO A6 size: 105 mm by 148 mm as defined in
ISO 216
'iso-a7': Specifies the ISO A7 size: 74 mm by 105 mm as defined in
ISO 216
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'iso-a8': Specifies the ISO A8 size: 52 mm by 74 mm as defined in
ISO 216
'iso-a9': Specifies the ISO A9 size: 37 mm by 52 mm as defined in
ISO 216
'iso-a10': Specifies the ISO A10 size: 26 mm by 37 mm as defined in
ISO 216
'iso-b0': Specifies the ISO B0 size: 1000 mm by 1414 mm as defined
in ISO 216
'iso-b1': Specifies the ISO B1 size: 707 mm by 1000 mm as defined
in ISO 216
'iso-b2': Specifies the ISO B2 size: 500 mm by 707 mm as defined in
ISO 216
'iso-b3': Specifies the ISO B3 size: 353 mm by 500 mm as defined in
ISO 216
'iso-b4': Specifies the ISO B4 size: 250 mm by 353 mm as defined in
ISO 216
'iso-b5': Specifies the ISO B5 size: 176 mm by 250 mm as defined in
ISO 216
'iso-b6': Specifies the ISO B6 size: 125 mm by 176 mm as defined in
ISO 216
'iso-b7': Specifies the ISO B7 size: 88 mm by 125 mm as defined in
ISO 216
'iso-b8': Specifies the ISO B8 size: 62 mm by 88 mm as defined in
ISO 216
'iso-b9': Specifies the ISO B9 size: 44 mm by 62 mm as defined in
ISO 216
'iso-b10': Specifies the ISO B10 size: 31 mm by 44 mm as defined in
ISO 216
'na-letter': Specifies the North American letter size: 8.5 inches
by 11 inches
'na-legal': Specifies the North American legal size: 8.5 inches by
14 inches
'executive': Specifies the executive size (7.25 X 10.5 in)
'folio': Specifies the folio size (8.5 X 13 in)
'invoice': Specifies the invoice size (5.5 X 8.5 in)
'ledger': Specifies the ledger size (11 X 17 in)
'quarto': Specifies the quarto size (8.5 X 10.83 in)
'iso-c3': Specifies the ISO C3 size: 324 mm by 458 mm as defined in
ISO 269
'iso-c4': Specifies the ISO C4 size: 229 mm by 324 mm as defined in
ISO 269
'iso-c5': Specifies the ISO C5 size: 162 mm by 229 mm as defined in
ISO 269
'iso-c6': Specifies the ISO C6 size: 114 mm by 162 mm as defined in
ISO 269
'iso-designated-long': Specifies the ISO Designated Long size: 110
mm by 220 mm as defined in ISO 269
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'na-10x13-envelope': Specifies the North American 10x13 size: 10
inches by 13 inches
'na-9x12-envelope': Specifies the North American 9x12 size: 9
inches by 12 inches
'na-number-10-envelope': Specifies the North American number 10
business envelope size: 4.125 inches by 9.5 inches
'na-7x9-envelope': Specifies the North American 7x9 inch envelope
size
'na-9x11-envelope': Specifies the North American 9x11 inch envelope
size
'na-10x14-envelope': Specifies the North American 10x14 inch
envelope size
'na-number-9-envelope': Specifies the North American number 9
business envelope size
'na-6x9-envelope': Specifies the North American 6x9 envelope size
'na-10x15-envelope': Specifies the North American 10x15 envelope
size
'monarch-envelope': Specifies the Monarch envelope size (3.87 x 7.5
in)
'jis-b0': Specifies the JIS B0 size: 1030mm x 1456mm
'jis-b1': Specifies the JIS B1 size: 728mm x 1030mm
'jis-b2': Specifies the JIS B2 size: 515mm x 728mm
'jis-b3': Specifies the JIS B3 size: 364mm x 515mm
'jis-b4': Specifies the JIS B4 size: 257mm x 364mm
'jis-b5': Specifies the JIS B5 size: 182mm x 257mm
'jis-b6': Specifies the JIS B6 size: 128mm x 182mm
'jis-b7': Specifies the JIS B7 size: 91mm x 128mm
'jis-b8': Specifies the JIS B8 size: 64mm x 91mm
'jis-b9': Specifies the JIS B9 size: 45mm x 64mm
'jis-b10': Specifies the JIS B10 size: 32mm x 45mm
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