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Network Working Group Tim Howes Request for Comments: DRAFT Mark Smith draft-ietf-asid-mime-direct-04.txt Netscape Communications Corp. July, 1997 A MIME Content-Type for Directory Information <draft-ietf-asid-mime-direct-04.txt> 1. Status of this Memo This document is an Internet-Draft. Internet-Drafts are working docu- ments 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). 2. Abstract This document defines a MIME Content-Type for holding directory informa- tion. The definition is independent of any particular directory service or protocol. The text/directory Content-Type is defined for holding a variety of directory information, for example, name, or email address, or logo. The text/directory Content-Type can also be used as the root body part in a multipart/related Content-Type for handling more compli- cated situations, especially those in which non-textual information that already has a natural MIME representation, for example, a photograph or sound, must be represented. The text/directory Content-Type defines a general framework and format for holding directory information in a simple "type: value" form. Mechanisms are defined to specify alternate character sets, languages, encodings and other meta-information. This document also defines the procedure by which particular formats, called profiles, for carrying application-specific information within a text/directory Content-Type may be defined and registered, and the conventions such formats must Howes & Smith [Page 1] Expires in six months INTERNET DRAFT follow. It is expected that other documents will be produced that define such formats for various applications (e.g., white pages). 3. Need for a MIME Directory Type For purposes of this document, a directory is a special-purpose database that contains typed information. A directory usually supports both read and search of the information it contains, and may support modification of the information as well. Directory information is usually accessed far more often than it is updated. Directories may be local or global in scope. They may be distributed or centralized. The information they contain may be replicated, with weak or strong consistency requirements. There are several situations in which users of Internet mail may wish to exchange directory information: the email analogy of a "business card" exchange; the conveyance of directory information to a user having only email access to the Internet; the provision of machine-parseable address information when purchasing goods or services over the Internet; etc. As MIME [RFC-2045,RFC-2046] is used increasingly by other protocols, most notably HTTP, it may also be useful for these protocols to be able to carry directory information in MIME format. Such a format, for example, could be used to represent URC (uniform resource characteristics) infor- mation about resources on the World Wide Web, or to provide a rudimen- tary directory service over HTTP. 4. Overview The scheme defined here for representing directory information in a MIME Content-Type has two parts. First, the text/directory Content-Type is defined for use in holding directory information within a single body part, for example name, title, or email address. In its simplest form, the format uses a "type: value" approach, which should be easily pars- able by existing MIME implementations and understandable by users. More complicated situations can be represented also. This document defines the general form the information in the Content-Type should have, and the procedure by which specific types and values (properties) for par- ticular applications may be defined. The framework is general enough to handle information from any number of end directory services, including LDAP [RFC-1777, RFC-1778], WHOIS++ [RFC-1835], and X.500 [X500]. Directory entries can include far more than just textual information. Some such information (e.g., an image or sound) overlaps with predefined MIME Content-Types. In these cases it may be desirable to include the information in its well-known MIME format. This situation is handled by using a multipart/related Content-Type as defined in [RFC-1872]. The root component of this type is a text/directory body part specifying any in-line information, and for information contained in other Content- Types, the Content-IDs (in URI form) of those types. Howes & Smith [Page 2] Expires in six months INTERNET DRAFT In some applications, it may be useful to include a pointer (e.g, a URI) to some directory information rather than the information itself. This document defines a general mechanism for accomplishing this. 5. The text/directory Content-Type The text/directory Content-Type is used to hold basic directory informa- tion, URIs referencing other information, including other MIME body parts holding supplementary or non-textual directory information, such as an image or sound. It is defined as follows, using the MIME media type registration template from [RFC-2048]. To: ietf-types@uninett.no Subject: Registration of MIME media type text/directory 5.1. MIME media type name MIME media type name: text 5.2. MIME subtype name MIME subtype name: directory 5.3. Required parameters Required parameters: charset The "charset" parameter is as defined in [RFC-2046] for other body parts. It is used to identify the default character set used within the body part. 5.4. Optional parameters Optional parameters: profile The "profile" parameter is used to convey the type(s) of entity(ies) to which the directory information pertains and the likely set of informa- tion associated with the entity(ies). It is intended only as a guide to applications interpreting the information contained within the body part. It SHOULD NOT be used to exclude or require particular pieces of information unless a profile definition specifically calls for this behavior. Unless specifically forbidden by a particular profile defini- tion, a text/directory content type may contain arbitrary attribute/value pairs. The value of the "profile" parameter is defined as follows. Profile names are case insensitive (i.e., the profile name "Person" is the same as "PERSON" and "person" and "peRsOn"). Howes & Smith [Page 3] Expires in six months INTERNET DRAFT profile := x-token / iana-token x-token := <The two characters "X-" or "x-" followed, with no intervening white space, by any atom, where atom is from Section 3.3 of RFC 822> iana-token := <a publicly-defined extension token, registered with IANA, as specified in Section 9 of this document> 5.5. Encoding considerations The default encoding is 8bit. Otherwise, as specified by the Content- Transfer-Encoding header field. Note that each value may also have an inline encoding associated with it. This encoding is independent of the encoding for the body part as a whole. When encoding, inline per-value encodings are performed first, then Content-Transfer-Encoding is applied to the entire body part. When decoding, the Content-Transfer-Encoding for the entire body part is decoded, then any value-specific encodings are decoded. 5.6. Security considerations Directory information may be public or it may be protected from unau- thorized access by the directory service in which it resides. Once the information leaves its native service, there can be no guarantee that the same care will be taken by all services handling the information. Furthermore, this specification defines no access control mechanism by which information may be protected, or by which access control informa- tion may be conveyed. Note that the integrity and privacy of a text/directory body part may be protected by enclosing it within an appropriate MIME-based security mechanism. 5.7. Interoperability considerations In order to make sense of directory information, applications must share a common understanding of the types of information contained within the Content-Type (the directory schema). This schema information is not defined in this document, but rather in companion documents (e.g., [MIME-VCARD]) that follow the requirements specified in this document, or in bilateral agreements between communicating parties. 5.8. Published specification The text/directory Content-Type contains directory information, typi- cally pertaining to a single directory entity or group of entities. The content consists of one or more lines in the format given below. Howes & Smith [Page 4] Expires in six months INTERNET DRAFT 5.8.1. Line delimiting and folding Individual lines within the MIME text/directory Content Type body are delimited by the [RFC-822] line break, which is a CRLF sequence (ASCII decimal 13, followed by ASCII decimal 10). Long logical lines of text can be split into a multiple-physical-line representation using the fol- lowing folding technique. A logical line may be continued on the next physical line at any point by inserting a CRLF immediately followed by a single white space charac- ter (space, ASCII decimal 32, or horizontal tab, ASCII decimal 9). Any sequence of CRLF followed immediately by a single white space character is ignored (removed) when processing the content type. For example the line: DESCRIPTION:This is a long description that exists on a long line. Can be represented as: DESCRIPTION:This is a long description that exists on a long line. The process of moving from this folded multiple-line representation of a type definition to its single line representation is called unfolding. Unfolding is accomplished by regarding CRLF immediately followed by a white space character as equivalent to no characters at all (i.e., the CRLF and single white space character are removed). A formatted text line break in an attribute value should also be speci- fied by a (RFC 822) line break, which is a CRLF sequence. However, since the CRLF sequence is used to delimit a content-type line, attribute values with formatted line breaks (i.e., multiple lines) must be encoded using an alternate encoding of either Quoted-Printable or Base64, as defined in [RFC 2046]. For example, in the Quoted-Printable encoding the multiple lines of for- matted text are separated with a Quoted-Printable CRLF sequence of =0D followed by =0A followed by a Quoted-Printable soft line break sequence of =. Quoted-Printable lines of text must also be limited to less than 76 characters. The 76 characters does not include the CRLF [RFC 822] line break sequence. For example a multiple line DESCRIPTION value of: Mythical Manager Hyjinx Software Division BabsCo, Inc. Would be represented in a Quoted-Printable encoding as: Howes & Smith [Page 5] Expires in six months INTERNET DRAFT DESCRIPTION; encoding=QUOTED-PRINTABLE:Mythical Manager=0D=0A= Hyjinx Software Division=0D=0A= BabsCo, Inc. 5.8.2. BNF content-type definition Using the notation of RFC 822, the syntax for this content is: contentline := [group.]type [";" parameterlist] ":" valuespec group := atom ; as defined in Section 3.3 of RFC 822 type := x-name / iana-type x-name := <the two characters "X-" or "x-" followed, with no intervening white space, by any atom> iana-type := <a publicly-defined extension token, registered with IANA, as specified in Section 11 of this document> parameterlist := parameter / parameterlist ";" parameter parameter := encodingparm / valuetypeparm / languageparm / contextparm / [parmtype "="] parmvalues encodingparm := "encoding" "=" encodingtype encodingtype := "base64" ; from Section 6.8 of RFC 2045 / "quoted-printable" ; from Section 6.7 of RFC 2045 / "8bit" / "7bit" valuetypeparm := "value" "=" valuetype valuetype := "uri" ; generic uri from RFC 1738 / "text" / "date" / "time" / "date-time" ; date time / "integer" / "boolean" / "float" / x-name Howes & Smith [Page 6] Expires in six months INTERNET DRAFT / iana-valuetype iana-valuetype : = <a publicly-defined extension token, registered with IANA, as defined in Section 15 of this document> languageparm := "language" "=" language ; as defined in RFC 1766 contextparm := "context" "=" context context := iana-token ; a token registered with IANA / x-name parmtype := x-name / iana-parmtype iana-parmtype := <a publicly-defined extension token, registered with IANA, as defined in Section 12 of this document> parmvalues := parmvalue / parmvalues "," parmvalue parmvalue := x-name / iana-parmvalue iana-parmvalue := <a publicly-defined extension token, registered with IANA, as defined in Section 13 of this document> valuespec := *text ; Characters whose syntax depends on type and the ; the encoding parameter. If the value contains ; a CRLF sequence (ASCII 10 followed by 13), it must ; be encoded using either base64 or quoted-printable. / date-spec / time-spec / date-time-spec / boolean / integer / float / iana-valuespec date-spec := date *[ "," date ] ; date as defined in [DATETIME] time-spec := time *[ "," time ] ; time as defined in [DATETIME] date-timed-spec := date time ; as above Howes & Smith [Page 7] Expires in six months INTERNET DRAFT boolean := "TRUE" / "FALSE" integer := [ sign ] 1*DIGIT *[ "," integer ] ; DIGIT as defined in RFC 822 float := [sign] 1*DIGIT ["." *DIGIT] *("," float) sign := "+" / "-" iana-valuespec := <a publicly-defined valuetype format, registered with IANA, as defined in section 15 of this document> To the left of the beginning of "value", white space characters (namely HTABs and SPACEs, ASCII 9 and 32) may freely surround any symbol. Note that this means that if a "value" begins with white space, it must be encoded using either the base64 or quoted-printable methods. A line that begins with a white space character is a continuation of the previous line, as described above. The white space character and line- ending CRLF should be discarded when reconstructing the original line. Note that this line-folding convention differs from that found in RFC 822, in that the sequence <CRLF><whitespacecharacter> found anywhere in the content indicates a continued line and should be removed. Since the CRLF sequence is used to separate lines within the content type, if this sequence appears in a value, the value must be encoded using either base64 or quoted-printable. The meanings of the various type names and the format of the correspond- ing values must be defined as specified in Section 11. Specifications may impose ordering on the type constructs within a body part, though none is required by default. The various x-name constructs are used for bilaterally-agreed upon type names, parameter names and parameter values. Type names, parameter names, and parameter values (i.e., everything to the left of the ":") are case insensitive (e.g., the type name "cn" is the same as "CN" and "Cn"). The group construct is used to group related attributes together. The group name is a syntactic convention used to indicate that all type names prefaced with the same group name should be grouped together when displayed by an application. It has no other significance. Implementa- tions that do not understand or support grouping may simply strip off any text before a "." and present the types and values as normal. Each attribute defined in the text/directory body may have multiple values, if allowed in the definition of the profile in which the Howes & Smith [Page 8] Expires in six months INTERNET DRAFT attribute is used. The general rule for encoding multi-valued items is to simply create a new content line for each value (including the type name). However, it should be noted that some value types may support encoding multiple values in a single content line, for example by separating the values with a comma "," or other delimiter. This approach has been taken for several of the content types defined above (date, time, integer, float), for space-saving reasons. The "language" type parameter should be used to identify data in alter- nate languages. There is no concept of "default" language, except as specified by any "Content-Language" MIME header parameter that may be present. The value of the "language" type parameter is a language tag as defined in Section 2 of [RFC-1766]. The "context" type parameter should be used to identify a context (e.g., a protocol) used in interpreting the value. This is used, for example, in the "name" type, defined below. The "encoding" type parameter should be used to specify an alternate encoding for a value. If the value contains a CRLF sequence (ASCII 10 followed by 13), it must be encoded using either "base64" or "quoted- printable", since CRLF is used to separate lines in the content-type itself. These encodings can also be useful for binary values that are mixed with other text information in the body part (e.g., a certifi- cate). Using a per-value "base64" or "quoted-printable" encoding in this case leaves the other information in a more readable form. The Content-Transfer-Encoding header field is used to specify the encod- ing used for the body part as a whole. The "encoding" type parameter is used to specify an encoding for a particular value (e.g., a certifi- cate). In this case, the Content-Transfer-Encoding header might specify "8bit", while the one certificate value might specify an encoding of base64 via an "encoding=base64" type parameter. Each type has associated with it a default encoding, which shall be used in the absence of an overriding "encoding" type parameter. This default encoding is given in the type definition, as defined in Section 11 of this document. The "value" parameter is optional, and may be used to identify the value type (data type) and format of the value. The use of these predefined formats is encouraged even if the value parameter is not explicity used. By defining a standard set of value types and their formats, existing parsing and processing code may be leveraged. Including the value type explicitly as part of each property provides an extra hint to keep parsing simple and support more generalized applica- tions. For example a search engine would not have to know the Howes & Smith [Page 9] Expires in six months INTERNET DRAFT particular value types for all of the items for which it is searching. Because the value type is explicit in the definition, the search engine could look for dates in any item type and provide good results. 5.8.3. Predefined value formats Some specific notes on the value types and formats: "text": The "text" value type should be used to identify values that contain human-readable text. The character set and language in which the text is represented is controlled by the charset content-header and the language type parameters and content-header. "uri": The "uri" value type should be used to identify values that are referenced by a URI (including a Content-ID URI), instead of encoded in-line. These value references might be used if the value is too large, unavailable, or otherwise undesirable to include directly. The format for the URI is as defined in RFC 1738. "date", "time", and "date-time": Each of these value types is based on the definitions in [DATETIME], which defines an Internet profile of the ISO 8601 standard. Profiles may place further restrictions on "date" and "time" values than are found in [DATETIME]. Multiple "date" and "time" values may be specified using the comma-separated notation. Examples for "date": 1985-04-12 1996-08-05, 1996-11-11 19850412 Examples for "time": 10:22:00 102200 10:22:00.33 10:22:00.33Z 10:22:33, 11:22:00 10:22:00-08:00 Examples for "date-time": 1996-10-22T14:00:00Z 1996-08-11T12:34:56Z 19960811T123456Z 1996-10-22T14:00:00Z, 1996-08-11T12:34:56Z "boolean": The "boolean" value type is used to express boolen values. These values are case insensitive. Examples: TRUE Howes & Smith [Page 10] Expires in six months INTERNET DRAFT false true "integer": The "integer" value type is used to express 32-bit signed integers in decimal format. The valid range for "int" is -2147483648 to 2147483647. If sign is not specified, the value is assumed positive "+". Multiple "integer" values may be specified using the comma- separated notation. Examples: 1234567890 -1234556790 +1234556790, 432109876 "float": The "float" value type is used to express real numbers. If sign is not specified, the value is assumed positive "+". Multiple "float" values may be specified using the comma-separated notation. Examples: 20.30 1000000.0000001 1.333, 3.14 5.9. Applications which use this media type Applications which use this media type: Various 5.10. Additional information Additional information: None 5.11. Person & email address to contact for further information Tim Howes Netscape Communications Corp. 501 East Middlefield Rd. Mountain View, CA 94041 USA howes@netscape.com +1 415 937 3419 5.12. Intended usage Intended usage: COMMON 5.13. Author/Change controller Tim Howes Netscape Communications Corp. Howes & Smith [Page 11] Expires in six months INTERNET DRAFT 501 East Middlefield Rd. Mountain View, CA 94041 USA howes@netscape.com +1 415 937 3419 Mark Smith Netscape Communications Corp. 501 East Middlefield Rd. Mountain View, CA 94041 USA mcs@netscape.com +1 415 937 3477 6. Predefined Types The following types are generally useful regardless of the profile being carried, and are defined below using the text/directory MIME type regis- tration template defined in Section 11.1 of this document. These types may be included in any profile, unless explicitly forbidden in the pro- file definition. 6.1. SOURCE Type Definition To: ietf-mime-direct@imc.org Subject: Registration of text/directory MIME type SOURCE Type name: SOURCE Type purpose: To identify the source of directory information con- tained in the content type. Type encoding: 8bit Type valuetype: text containing a URI. Type special notes: The SOURCE type is used to provide the means by which applications knowledgable in the given directory service proto- col may obtain additional or more up-to-date information from the directory service. It contains a URI as defined in [RFC-1738] referencing the directory entity or entities to which the information pertains. When directory information is available from more than one source, the sending entity may pick what it considers to be the best source, or multiple SOURCE types may be included. Type example: SOURCE: ldap://ldap.host/cn=Babs%20Jensen,%20o=Babsco,%20c=US Howes & Smith [Page 12] Expires in six months INTERNET DRAFT 6.2. NAME Type Definition To: ietf-mime-direct@imc.org Subject: Registration of text/directory MIME type NAME Type name: NAME Type purpose: To identify the displayable name of the directory entity to which information in the content type pertains. Type encoding: 8bit Type valuetype: text Type special notes: The NAME type is used to convey the directory name of the entity to which the directory information pertains. Its value depends on the setting of the "CONTEXT" type parameter, which indicates the directory service protocol context in which the value of the NAME parameter should be interpreted. Note that this value is protocol-specific and is intended for applications knowledgable in a particular directory service protocol. Type example: NAME;CONTEXT=LDAP: cn=Babs Jensen, o=Babsco, c=US 6.3. PROFILE Type Definition To: ietf-mime-direct@imc.org Subject: Registration of text/directory MIME type PROFILE Type name: PROFILE Type purpose: To identify the type of directory entity to which information in the content type pertains. Type encoding: 8bit Type valuetype: text, containing a profile name, registered as described in Section 9 of this document or bilaterally-agreed upon as described in Section 5. Type special notes: The PROFILE type is used to convey the type of the entity to which the directory information in the rest of the body part pertains. It should be the same as the "profile" header parame- ter, if present. Type example: PROFILE: person Howes & Smith [Page 13] Expires in six months INTERNET DRAFT 6.4. BEGIN Type Definition To: ietf-mime-direct@imc.org Subject: Registration of text/directory MIME type BEGIN Type name: BEGIN Type purpose: To delimit the beginning of a syntactic entity within a text/directory content-type. Type encoding: 8bit Type valuetype: text, containing a profile name, registered as described in Section 9 of this document or bilaterally-agreed upon as described in Section 5. Type special notes: The BEGIN type is used in conjunction with the END type to delimit a profile containing a related set of directory content within an text/directory content-type. This construct may be used instead of or in addition to wrapping separate sets of informa- tion inside additional MIME headers. It is provided for applications that wish to define content that may contain multiple entities within the same text/directory content-type or to define content that may be identifiable outside of a MIME environment. Type example: BEGIN: vcard 6.5. END Type Definition To: ietf-mime-direct@imc.org Subject: Registration of text/directory MIME type END Type name: END Type purpose: To identify the type of directory entity to which information in the content type pertains. Type encoding: 8bit Type valuetype: text, containing a profile name, registered as described in Section 9 of this document or bilaterally-agreed upon as described in Section 5. Type special notes: The END type is used in conjunction with the BEGIN type to delimit a profile containing a related set of directory content within an text/directory content-type. This construct may be used instead of or in addition to wrapping separate sets of Howes & Smith [Page 14] Expires in six months INTERNET DRAFT information inside additional MIME headers. It is provided for appli- cations that wish to define content that may contain multiple enti- ties within the same text/directory content-type or to define content that may be identifiable outside of a MIME environment. Type example: END: vcard 7. Use of the multipart/related Content-Type The multipart/related Content-Type can be used to hold directory infor- mation comprised of both text and non-text information or directory information that already has a natural MIME representation. The root body part within the multipart/related body part is specified as defined in [RFC-1872] by a "start" parameter, or it is the first body part in the absence of such a parameter. The root body part must have a Content-Type of "text/directory". This part holds inline information, optionally defines the name and source of the information, and makes reference to subsequent body parts holding additional text or non-text directory information via their Content-ID URIs as explained in Section 5. The body parts referred to do not have to be in any particular order, except as noted above for the root body part. 8. Examples The following examples are for illustrative purposes only and are not part of the definition. 8.1. Example 1 The first example illustrates simple use of the text/directory Content- Type. Note that no "profile" parameter is given, so an application may not know what kind of directory entity the information applies to. Note also the use of both hypothetical official and bilaterally agreed upon types. From: Whomever@wherever.com To: Someone@somewhere.com Subject: whatever MIME-Version: 1.0 Message-ID: <id1@host.net> Content-Type: text/directory Content-ID: <id2@host.com> cn: Babs Jensen cn: Barbara J Jensen Howes & Smith [Page 15] Expires in six months INTERNET DRAFT sn: Jensen email: babs@umich.edu phone: +1 313 747-4454 x-id: 1234567890 8.2. Example 2 The next example illustrates the use of the Quoted-Printable encoding defined in [RFC 2045] to include non-ASCII character in some of the information returned, and the use of the optional "name" and "source" types. It also illustrates the use of an "encoding" type parameter to encode a certificate value in base64. A "vCard" profile [MIME-VCARD] is used for the example. Content-Type: text/directory; charset="iso-8859-1"; profile="vCard" Content-ID: <id3@host.com> Content-Transfer-Encoding: Quoted-Printable begin: vcard source: ldap://cn=3Dbjorn%20Jensen, o=3Duniversity%20of%20Michigan, c=3DUS name: cn=3Dbjorn Jensen, o=3Duniversity of Michigan, c=3DUS fn: Bj=F8rn Jensen n: Jensen;Bj=F8rn email;type=3Dinternet: bjorn@umich.edu tel;type=3Dwork,voice,msg:+1 313 747-4454 key;type=3Dx509;encoding=3Dbase64: dGhpcyBjb3VsZCBiZSAKbXkgY2VydGlmaWNhdGUK end: vcard 8.3. Example 3 The next example illustrates the use of multi-valued type parameters, the "language" type parameter, the "value" type parameter, inline quoted-printable encoding to represent iso-8859-1 characters and fold long lines, and attribute grouping. Content-Type: text/directory; profile="person"; charset=iso-8859-1 Content-ID: <id3@host.com> source: ldap://cn=Meister%20Berger,o=Universitaet%20Goerlitz,c=DE name: cn=Meister Berger, o=Universitaet Goerlitz, c=DE cn: Meister Berger cn: Berger Meister sn: Berger age;value=integer: 33 o;encoding=quoted-printable: Universit=E6t G=F6rlitz title: Mayor Howes & Smith [Page 16] Expires in six months INTERNET DRAFT title;language=de;value=text: Burgermeister description;encoding=quoted-printable: The Mayor of the great city of= Goerlitz in the great country of Germany. email: mb@goerlitz.de home.phone;fax,voice,msg: +49 3581 123456 home.addr;encoding=quoted-printable: Hufenshlagel 1234=0A= 02828 Goerlitz=0A= Deutschland certificate;encoding=base64: dGhpcyBjb3VsZCBiZSAKbXkgY2VydGlma... 8.4. Example 4 The final example illustrates the use of the multipart/related Content- Type to include non-textual directory data via the "uri" encoding to refer to other body parts within the same message, or to external values. Content-Type: multipart/related; boundary=woof; type="text/directory"; start="<id5@host.com>" Content-ID: <id4@host.com> --woof Content-Type: text/directory; charset="iso-8859-1" Content-ID: <id5@host.com> Content-Transfer-Encoding: Quoted-Printable source: ldap://cn=3DBjorn%20Jensen,o=3DUniversity%20of%20Michigan,c=3DUS cn: Bj=F8rn Jensen sn: Jensen email: bjorn@umich.edu image;encoding=3Duri: cid:id6@host.com image;encoding=3Duri;format=3Djpeg: ftp://some.host/some/path.jpg sound;encoding=3Duri: cid:id7@host.com phone: +1 313 747-4454 --woof Content-Type: image/jpeg Content-ID: <id6@host.com> <...image data...> --woof Content-Type: message/external-body; name="myvoice.au"; site="myhost.com"; access-type=ANON-FTP; Howes & Smith [Page 17] Expires in six months INTERNET DRAFT directory="pub/myname"; mode="image" Content-Type: audio/basic Content-ID: <id7@host.com> --woof-- 9. Registration of new profiles This section defines procedures by which new profiles are registered with the IANA and made available to the Internet community. Note that non-IANA profiles may be used by bilateral agreement, provided the asso- ciated profile names follow the "X-" convention defined above. The procedures defined here are designed to allow public comment and review of new profiles, while posing only a small impediment to the definition of new profiles. Registration of a new profile is accomplished by the following steps. 9.1. Define the profile A profile is defined by completing the following template. To: ietf-mime-direct@imc.org Subject: Registration of text/directory MIME profile XXX Profile name: Profile purpose: Profile types: Profile special notes (optional): Intended usage: (one of COMMON, LIMITED USE or OBSOLETE) The explanation of what goes in each field in the template follows. Profile name: The name of the profile as it will appear in the text/directory MIME Content-Type "profile" header parameter, or the predefined "profile" type name. Profile purpose: The purpose of the profile (e.g., to represent informa- tion about people, printers, documents, etc.). Give a short but clear description. Howes & Smith [Page 18] Expires in six months INTERNET DRAFT Profile types: The list of types associated with the profile. This list of types is to be expected but not required in the profile, unless oth- erwise noted in the profile definition. Other types not mentioned in the profile definition may also be present. Note that any new types referenced by the profile must be defined separately as described in Section 10. Profile special notes: Any special notes about the profile, how it is to be used, etc. This section of the template may also be used to define an ordering on the types that appear in the Content-Type, if such an order- ing is required. 9.2. Post the profile definition The profile description must be posted to the new profile discussion list, ietf-mime-direct@imc.org 9.3. Allow a comment period Discussion on the new profile must be allowed to take place on the list for a minimum of two weeks. Consensus must be reached on the profile before proceeding to step 4. 9.4. Submit the profile for approval Once the two-week comment period has elapsed, and the proposer is con- vinced consensus has been reached on the profile, the registration application should be submitted to the Profile Reviewer for approval. The Profile Reviewer is appointed to the Application Area Directors and may either accept or reject the profile registration. An accepted regis- tration should be passed on by the Profile Reviewer to the IANA for inclusion in the official IANA profile registry. The registration may be rejected for any of the following reasons. 1) Insufficient comment period; 2) Consensus not reached; 3) Technical deficiencies raised on the list or elsewhere have not been addressed. The Profile Reviewer's decision to reject a profile may be appealed by the proposer to the IESG, or the objections raised can be addressed by the proposer and the profile resubmitted. 10. Profile Change Control Existing profiles may be changed using the same process by which they were registered. Define the change Post the change Howes & Smith [Page 19] Expires in six months INTERNET DRAFT Allow a comment period Submit the changed profile for approval Note that the original author or any other interested party may propose a change to an existing profile, but that such changes should only be proposed when there are serious omissions or errors in the published specification. The Profile Reviewer may object to a change if it is not backwards compatible, but is not required to do so. Profile definitions can never be deleted from the IANA registry, but profiles which are no longer believed to be useful can be declared OBSOLETE by a change to their "intended use" field. 11. Registration of new types This section defines procedures by which new types are registered with the IANA. Note that non-IANA types may be used by bilateral agreement, provided the associated types names follow the "X-" convention defined above. The procedures defined here are designed to allow public comment and review of new types, while posing only a small impediment to the defini- tion of new types. Registration of a new type is accomplished by the following steps. 11.1. Define the type A type is defined by completing the following template. To: ietf-mime-direct@imc.org Subject: Registration of text/directory MIME type XXX Type name: Type purpose: Type encoding: Type valuetype: Type special notes (optional): Intended usage: (one of COMMON, LIMITED USE or OBSOLETE) The meaning of each field in the template is as follows. Howes & Smith [Page 20] Expires in six months INTERNET DRAFT Type name: The name of the type, as it will appear in the body of an text/directory MIME Content-Type "type: value" line to the left of the colon ":". Type purpose: The purpose of the type (e.g., to represent a name, postal address, IP address, etc.). Give a short but clear description. Type encoding: The default encoding a value of the type must have in the body of a text/directory MIME Content-Type. Type valuetype: The format a value of the type must have in the body of a text/directory MIME Content-Type. This description must be precise and must not violate the general encoding rules defined in section 5 of this document. Type special notes: Any special notes about the type, how it is to be used, etc. 11.2. Post the type definition The type description must be posted to the new type discussion list, ietf-mime-direct@imc.org 11.3. Allow a comment period Discussion on the new type must be allowed to take place on the list for a minimum of two weeks. Consensus must be reached on the type before proceeding to step 4. 11.4. Submit the type for approval Once the two-week comment period has elapsed, and the proposer is con- vinced consensus has been reached on the type, the registration applica- tion should be submitted to the Profile Reviewer for approval. The Pro- file Reviewer is appointed to the Application Area Directors and may either accept or reject the type registration. An accepted registration should be passed on by the Profile Reviewer to the IANA for inclusion in the official IANA profile registry. The registration may be rejected for any of the following reasons. 1) Insufficient comment period; 2) Con- sensus not reached; 3) Technical deficiencies raised on the list or elsewhere have not been addressed. The Profile Reviewer's decision to reject a type may be appealed by the proposer to the IESG, or the objec- tions raised can be addressed by the proposer and the type resubmitted. 12. Type Change Control Existing types may be changed using the same process by which they were registered. Howes & Smith [Page 21] Expires in six months INTERNET DRAFT Define the change Post the change Allow a comment period Submit the type for approval Note that the original author or any other interested party may propose a change to an existing type, but that such changes should only be pro- posed when there are serious omissions or errors in the published specification. The Profile Reviewer may object to a change if it is not backwards compatible, but is not required to do so. Type definitions can never be deleted from the IANA registry, but types which are nolonger believed to be useful can be declared OBSOLETE by a change to their "intended use" field. 13. Registration of new parameters This section defines procedures by which new parameters are registered with the IANA and made available to the Internet community. Note that non-IANA parameters may be used by bilateral agreement, provided the associated parameters names follow the "X-" convention defined above. The procedures defined here are designed to allow public comment and review of new parameters, while posing only a small impediment to the definition of new parameters. Registration of a new parameter is accomplished by the following steps. 13.1. Define the parameter A parameter is defined by completing the following template. To: ietf-mime-direct@imc.org Subject: Registration of text/directory MIME type parameter XXX Parameter name: Parameter purpose: Parameter values: Parameter special notes (optional): Intended usage: (one of COMMON, LIMITED USE or OBSOLETE) Howes & Smith [Page 22] Expires in six months INTERNET DRAFT The explanation of what goes in each field in the template follows. Parameter name: The name of the parameter as it will appear in the text/directory MIME Content-Type. Parameter purpose: The purpose of the parameter (e.g., to represent the format of an image, type of a phone number, etc.). Give a short but clear description. If defining a general paramemter like "format" or "type" keep in mind that other applications may wish to extend its use. Parameter values: The list or description of values associated with the parameter. Parameter special notes: Any special notes about the parameter, how it is to be used, etc. 13.2. Post the parameter definition The parameter description must be posted to the new parameter discussion list, ietf-mime-direct@imc.org 13.3. Allow a comment period Discussion on the new parameter must be allowed to take place on the list for a minimum of two weeks. Consensus must be reached on the param- eter before proceeding to step 4. 13.4. Submit the parameter for approval Once the two-week comment period has elapsed, and the proposer is con- vinced consensus has been reached on the parameter, the registration application should be submitted to the Profile Reviewer for approval. The Profile Reviewer is appointed to the Application Area Directors and may either accept or reject the parameter registration. An accepted registration should be passed on by the Profile Reviewer to the IANA for inclusion in the official IANA parameter registry. The registration may be rejected for any of the following reasons. 1) Insufficient comment period; 2) Consensus not reached; 3) Technical deficiencies raised on the list or elsewhere have not been addressed. The Profile Reviewer's decision to reject a profile may be appealed by the proposer to the IESG, or the objections raised can be addressed by the proposer and the parameter registration resubmitted. 14. Parameter Change Control Existing parameters may be changed using the same process by which they were registered. Howes & Smith [Page 23] Expires in six months INTERNET DRAFT Define the change Post the change Allow a comment period Submit the parameter for approval Note that the original author or any other interested party may propose a change to an existing parameter, but that such changes should only be proposed when there are serious omissions or errors in the published specification. The Profile Reviewer may object to a change if it is not backwards compatible, but is not required to do so. Parameter definitions can never be deleted from the IANA registry, but parameters which are nolonger believed to be useful can be declared OBSOLETE by a change to their "intended use" field. 15. Registration of new value types This section defines procedures by which new value types are registered with the IANA and made available to the Internet community. Note that non-IANA value types may be used by bilateral agreement, provided the associated value types names follow the "X-" convention defined above. The procedures defined here are designed to allow public comment and review of new value types, while posing only a small impediment to the definition of new value types. Registration of a new value types is accomplished by the following steps. 15.1. Define the value type A value type is defined by completing the following template. To: ietf-mime-direct@imc.org Subject: Registration of text/directory MIME value type XXX value type name: value type purpose: value type format: value type special notes (optional): Howes & Smith [Page 24] Expires in six months INTERNET DRAFT Intended usage: (one of COMMON, LIMITED USE or OBSOLETE) The explanation of what goes in each field in the template follows. value type name: The name of the value type as it will appear in the text/directory MIME Content-Type. value type purpose: The purpose of the value type. Give a short but clear description. value type format: The definition of the format for the value, usually using BNF grammar. value type special notes: Any special notes about the value type, how it is to be used, etc. 15.2. Post the value type definition The value type description must be posted to the new value type discus- sion list, ietf-mime-direct@imc.org 15.3. Allow a comment period Discussion on the new value type must be allowed to take place on the list for a minimum of two weeks. Consensus must be reached before proceeding to step 4. 15.4. Submit the value type for approval Once the two-week comment period has elapsed, and the proposer is con- vinced consensus has been reached on the value type, the registra- tion application should be submitted to the Profile Reviewer for approval. The Profile Reviewer is appointed to the Application Area Directors and may either accept or reject the value type registration. An accepted registration should be passed on by the Profile Reviewer to the IANA for inclusion in the official IANA value type registry. The registration may be rejected for any of the following reasons. 1) Insufficient comment period; 2) Consensus not reached; 3) Technical deficiencies raised on the list or elsewhere have not been addressed. The Profile Reviewer's decision to reject a profile may be appealed by the proposer to the IESG, or the objections raised can be addressed by the proposer and the value type registration resubmit- ted. Howes & Smith [Page 25] Expires in six months INTERNET DRAFT 16. Security Considerations Internet mail is subject to many well known security attacks, including monitoring, replay, and forgery. Care should be taken by any directory service in allowing information to leave the scope of the service itself, where any access controls can no longer be guaranteed. Applica- tions should also take care to display directory data in a "safe" environment (e.g., PostScript-valued types). 17. Acknowledgements The registration procedures defined here were shamelessly lifted from the MIME registration RFC. The many valuable comments contributed by members of the IETF ASID work- ing group are gratefully acknowledged, as are the contributions of the Versit Consortium.. 18. Bibliography [RFC-1777] Yeong, W., Howes, T., Kille, S., "Lightweight Directory Access Protocol", Request for Comment (RFC) 1777, March 1995. [RFC-1778] Howes, T., Kille, S., Yeong, W., Robbins, C.J., "The String Representation of Standard Attribute Syntaxes", Request for Comment (RFC) 1778, March 1995. [RFC-822] Crocker, D., "Standard for the Format of ARPA Internet Text Messages", STD 11, RFC 822, August 1982. [RFC-1521] Borenstein, N., Freed, N., "Multipurpose Internet Mail Exten- sions (MIME) Part One: Format of Internet Message Bodies", RFC 2045, November 1996. [RFC-2046] Moore, K., "Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types", RFC 2046, November 1996. [RFC-2048] Freed, N., Klensin, J., Postel, J., "Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures", RFC 2048, November 1996 [RFC-1766] Alvestrand, H., "Tags for the Identification of Languages", RFC 1766, March 1995. [RFC-1872] Levinson, E., "The MIME Multipart/Related Content-type," RFC 1872, December 1995. [X500] "Information Processing Systems - Open Systems Howes & Smith [Page 26] Expires in six months INTERNET DRAFT Interconnection - The Directory: Overview of Concepts, Models and Services", ISO/IEC JTC 1/SC21, International Standard 9594-1, 1988. [RFC-1835] Deutsch, P., Schoultz, R., Faltstrom, P., Weider, C., "Archi- tecture of the WHOIS++ service", August 1995. [RFC-1738] Berners-Lee, T., Masinter, L., McCahill, M., "Uniform Resource Locators (URL)", RFC 1738, December 1994. [DATETIME] Newman, C., "Date and Time on the Internet", Internet Draft draft-newman-datetime-01.txt, January 1997. [MIME-VCARD]F. Dawson, T. Howes, "VCard MIME Directory Profile", Internet-Draft draft-ietf-asid-mime-vcard-02.txt, March, 1997. [VCARD] Versit Consortium, "vCard - The Electronic Business Card", Version 2.1, http://www.imc.com/pdi/vcard-21.txt, September, 1996. 19. Author's Address Tim Howes Netscape Communications Corp. 501 East Middlefield Rd. Mountain View, CA 94041 USA howes@netscape.com +1.415.937.3419 Mark Smith Netscape Communications Corp. 501 East Middlefield Rd. Mountain View, CA 94041 USA mcs@netscape.com +1.415.937.3477 20. Table of Contents 1. Status of this Memo............................................1 2. Abstract.......................................................1 3. Need for a MIME Directory Type.................................2 4. Overview.......................................................2 5. The text/directory Content-Type................................3 Howes & Smith [Page 27] 5.1. MIME media type name........................................3 5.2. MIME subtype name...........................................3 5.3. Required parameters.........................................3 5.4. Optional parameters.........................................3 5.5. Encoding considerations.....................................4 5.6. Security considerations.....................................4 5.7. Interoperability considerations.............................4 5.8. Published specification.....................................4 5.8.1. Line delimiting and folding..............................5 5.8.2. BNF content-type definition..............................6 5.8.3. Predefined value formats.................................10 5.9. Applications which use this media type......................11 5.10. Additional information......................................11 5.11. Person & email address to contact for further information...11 5.12. Intended usage..............................................11 5.13. Author/Change controller....................................11 6. Predefined Types...............................................12 6.1. SOURCE Type Definition......................................12 6.2. NAME Type Definition........................................13 6.3. PROFILE Type Definition.....................................13 6.4. BEGIN Type Definition.......................................14 6.5. END Type Definition.........................................14 7. Use of the multipart/related Content-Type......................15 8. Examples.......................................................15 8.1. Example 1...................................................15 8.2. Example 2...................................................16 8.3. Example 3...................................................16 8.4. Example 4...................................................17 9. Registration of new profiles...................................18 9.1. Define the profile..........................................18 9.2. Post the profile definition.................................19 9.3. Allow a comment period......................................19 9.4. Submit the profile for approval.............................19 10. Profile Change Control.........................................19 11. Registration of new types......................................20 11.1. Define the type.............................................20 11.2. Post the type definition....................................21 11.3. Allow a comment period......................................21 11.4. Submit the type for approval................................21 12. Type Change Control............................................21 13. Registration of new parameters.................................22 13.1. Define the parameter........................................22 13.2. Post the parameter definition...............................23 13.3. Allow a comment period......................................23 13.4. Submit the parameter for approval...........................23 14. Parameter Change Control.......................................23 15. Registration of new value types................................24 Howes & Smith [Page 28] 15.1. Define the value type.......................................24 15.2. Post the value type definition..............................25 15.3. Allow a comment period......................................25 15.4. Submit the value type for approval..........................25 16. Security Considerations........................................26 17. Acknowledgements...............................................26 18. Bibliography...................................................26 19. Author's Address...............................................27 20. Table of Contents..............................................27 Howes & Smith [Page 27]