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Draft Textual Conventions for SNMPv2 Dec 92 Textual Conventions for version 2 of the Simple Network Management Protocol (SNMPv2) Tue Dec 22 13:43:46 1992 | Jeffrey D. Case SNMP Research, Inc. University of Tennessee, Knoxville case@cs.utk.edu Keith McCloghrie Hughes LAN Systems kzm@hls.com Marshall T. Rose Dover Beach Consulting, Inc. mrose@dbc.mtview.ca.us Steven L. Waldbusser Carnegie Mellon University waldbusser@andrew.cmu.edu 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 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 a "work in progress". Expires June 22, 1993 [Page 1] Draft Textual Conventions for SNMPv2 Dec 92 1. Introduction A network management system contains: several (potentially many) nodes, each with a processing entity, termed an agent, which has access to management instrumentation; at least one management station; and, a management protocol, used to convey management information between the agents and management stations. Operations of the protocol are carried out under an administrative framework which defines both authentication and authorization policies. Network management stations execute management applications which monitor and control network elements. Network elements are devices such as hosts, routers, terminal servers, etc., which are monitored and controlled through access to their management information. Management information is viewed as a collection of managed objects, residing in a virtual information store, termed the Management Information Base (MIB). Collections of related objects are defined in MIB modules. These modules are written using a subset of OSI's Abstract Syntax Notation One (ASN.1) [1], termed the Structure of Management Information (SMI) [2]. When designing a MIB module, it is often useful to new define types similar to those defined in the SMI. In comparison to a type defined in the SMI, each of these new types has a different name, a similar syntax, but a more precise semantics. These newly defined types are termed textual conventions, and are used for the convenience of humans reading the MIB module. It is the purpose of this document to define the initial set of textual conventions available to all MIB modules. Objects defined using a textual convention are always encoded by means of the rules that define their primitive type. However, textual conventions often have special semantics associated with them. As such, an ASN.1 macro, TEXTUAL- CONVENTION, is used to concisely convey the syntax and semantics of a textual convention. For all textual conventions defined in an information module, the name shall be unique and mnemonic, and shall not exceed 64 characters in length. All names used for the textual conventions defined in all "standard" information modules Expires June 22, 1993 [Page 2] Draft Textual Conventions for SNMPv2 Dec 92 shall be unique. 1.1. A Note on Terminology For the purpose of exposition, the original Internet-standard Network Management Framework, as described in RFCs 1155, 1157, and 1212, is termed the SNMP version 1 framework (SNMPv1). The current framework is termed the SNMP version 2 framework (SNMPv2). Expires June 22, 1993 [Page 3] Draft Textual Conventions for SNMPv2 Dec 92 2. Definitions SNMPv2-TC DEFINITIONS ::= BEGIN IMPORTS ObjectSyntax, Integer32, TimeTicks FROM SNMPv2-SMI; -- definition of textual conventions TEXTUAL-CONVENTION MACRO ::= BEGIN TYPE NOTATION ::= DisplayPart "STATUS" Status "DESCRIPTION" Text ReferPart "SYNTAX" type(Syntax) VALUE NOTATION ::= value(VALUE Syntax) DisplayPart ::= "DISPLAY-HINT" Text | empty Status ::= "current" | "deprecated" | "obsolete" ReferPart ::= "REFERENCE" Text | empty -- uses the NVT ASCII character set Text ::= """" string """" END Expires June 22, 1993 [Page 4] Draft Textual Conventions for SNMPv2 Dec 92 DisplayString ::= TEXTUAL-CONVENTION DISPLAY-HINT "255a" STATUS current DESCRIPTION "Represents textual information taken from the NVT ASCII character set, as defined in pages 4, 10-11 of RFC 854. Any object defined using this syntax may not exceed 255 characters in length." SYNTAX OCTET STRING PhysAddress ::= TEXTUAL-CONVENTION DISPLAY-HINT "1x:" STATUS current DESCRIPTION "Represents media- or physical-level addresses." SYNTAX OCTET STRING MacAddress ::= TEXTUAL-CONVENTION DISPLAY-HINT "1x:" STATUS current DESCRIPTION "Represents an 802 MAC address represented in the `canonical' order defined by IEEE 802.1a, i.e., as if it were transmitted least significant bit first, even though 802.5 (in contrast to other 802.x protocols) requires MAC addresses to be transmitted most significant bit first." SYNTAX OCTET STRING (SIZE (6)) TruthValue ::= TEXTUAL-CONVENTION STATUS current DESCRIPTION "Represents a boolean value." SYNTAX INTEGER { true(1), false(2) } Expires June 22, 1993 [Page 5] Draft Textual Conventions for SNMPv2 Dec 92 TestAndIncr ::= TEXTUAL-CONVENTION STATUS current DESCRIPTION "Represents integer-valued information used for atomic operations. When the management protocol is used to specify that an object instance having this syntax is to be modified, the new value supplied via the management protocol must precisely match the value presently held by the instance. If not, the management protocol set operation fails with an error of `inconsistentValue'. Otherwise, if the current value is the maximum value of 2^31-1 (2147483647 decimal), then the value held by the instance is wrapped to zero; otherwise, the value held by the instance is incremented by one. (Note that regardless of whether the management protocol set operation succeeds, the variable-binding in the request and response PDUs are identical.) The value of the ACCESS clause for objects having this syntax is either `read-write' or `read- create'. When an instance of a columnar object having this syntax is created, any value may be supplied via the management protocol." SYNTAX INTEGER (0..2147483647) Expires June 22, 1993 [Page 6] Draft Textual Conventions for SNMPv2 Dec 92 AutonomousType ::= TEXTUAL-CONVENTION STATUS current DESCRIPTION "Represents an independently extensible type identification value. It may, for example, indicate a particular sub-tree with further MIB definitions, or define a particular type of protocol or hardware." SYNTAX OBJECT IDENTIFIER InstancePointer ::= TEXTUAL-CONVENTION STATUS current DESCRIPTION "A pointer to a specific instance of a conceptual row of a MIB table in the managed device. By convention, it is the name of the particular instance of the first columnar object in the conceptual row." SYNTAX OBJECT IDENTIFIER Expires June 22, 1993 [Page 7] Draft Textual Conventions for SNMPv2 Dec 92 RowStatus ::= TEXTUAL-CONVENTION STATUS current DESCRIPTION "The RowStatus textual convention is used to | manage the creation and deletion of conceptual | rows, and is used as the value of the SYNTAX | clause for the status column of a conceptual row | (as described in Section 7.7.1 of [2].) | The status column has six defined values: | - `active', which indicates that the | conceptual row is available for use by the | managed device; | - `notInService', which indicates that the | conceptual row exists in the agent, but is | unavailable for use by the managed device | (see NOTE below); | - `notReady', which indicates that the | conceptual row exists in the agent, but is | missing information necessary in order to be | available for use by the managed device; | - `createAndGo', which is supplied by a | management station wishing to create a new | instance of a conceptual row and to have it | available for use by the managed device; | - `createAndWait', which is supplied by a | management station wishing to create a new | instance of a conceptual row but not to have | it available for use by the managed device; | and, | - `destroy', which is supplied by a | management station wishing to delete all of | the instances associated with an existing | conceptual row. | Whereas five of the six values (all except | `notReady') may be specified in a management | protocol set operation, only three values will be | returned in response to a management protocol | Expires June 22, 1993 [Page 8] Draft Textual Conventions for SNMPv2 Dec 92 retrieval operation: `notReady', `notInService' or | `active'. That is, when queried, an existing | conceptual row has only three states: it is either | available for use by the managed device (the | status column has value `active'); it is not | available for use by the managed device, though | the agent has sufficient information to make it so | (the status column has value `notInService'); or, | it is not available for use by the managed device, | because the agent lacks sufficient information | (the status column has value `notReady'). | NOTE WELL | This textual convention may be used for a MIB + table, irrespective of whether the values of + that table's conceptual rows are able to be + modified while it is active, or whether its + conceptual rows must be taken out of service + in order to be modified. That is, it is the + responsibility of the DESCRIPTION clause of + the status column to specify whether the + status column must be `notInService' in order + for the value of some other column of the + same conceptual row to be modified. + Expires June 22, 1993 [Page 9] Draft Textual Conventions for SNMPv2 Dec 92 To summarize the effect of having a conceptual row + with a status column having a SYNTAX clause value + of RowStatus, consider the following state + diagram: + STATE + +--------------+-----------+-------------+-------------+ | A | B | C | D + | |status col.|status column| + |status column | is | is |status column+ ACTION |does not exist| notReady | notInService| is active+ --------------+--------------+-----------+-------------+-------------+ set status |noError ->D|inconsist- |inconsistent-|inconsistent-+ column to | or | entValue| Value| Value+ createAndGo |inconsistent- | | | + | Value| | | + --------------+--------------+-----------+-------------+-------------+ set status |noError see 1|inconsist- |inconsistent-|inconsistent-+ column to | or | entValue| Value| Value+ createAndWait |wrongValue | | | + --------------+--------------+-----------+-------------+-------------+ set status |inconsistent- |inconsist- |noError |noError + column to | Value| entValue| | + active | | | | + | | or | | + | | | | + | |see 2 ->C| ->D| ->D+ --------------+--------------+-----------+-------------+-------------+ set status |inconsistent- |inconsist- |noError |noError ->C+ column to | Value| entValue| | or+ notInService | | | ->C|wrongValue+ --------------+--------------+-----------+-------------+-------------+ set status |noError |noError |noError |noError + column to | | | | + destroy | ->A| ->A| ->A| ->A+ --------------+--------------+-----------+-------------+-------------+ set any other |see 3 |noError |noError |noError + column to some| | | | + value | ->A| see 1| ->C| ->D+ --------------+--------------+-----------+-------------+-------------+ (1) goto B or C, depending on information | available to the agent. | Expires June 22, 1993 [Page 10] Draft Textual Conventions for SNMPv2 Dec 92 (2) if other variable bindings in the same PDU | provide values for any missing but required | columns, then noError is returned and state C is | entered. | (3) at the discretion of the agent, either noError | or inconsistentValue may be returned. | NOTE: other processing of the set request may | prevent a noError response from being returned, | e.g., wrongValue, noCreation, etc. | Conceptual Row Creation | There are four potential interactions when | creating a conceptual row: selecting an instance- | identifier which is not in use; creating the | conceptual row; initializing any objects for which | the agent does not supply a default; and, making | the conceptual row available for use by the | managed device. | Interaction 1: Selecting an Instance-Identifier | The algorithm used to select an instance- | identifier varies for each conceptual row. In | some cases, the instance-identifier is | semantically significant, e.g., the destination | address of a route, and a management station | selects the instance-identifier according to the | semantics. | In other cases, the instance-identifier is used | solely to distinguish conceptual rows, and a | management station without specific knowledge of | the conceptual row might examine the instances | present in order to determine an unused instance- | identifier. (This approach may be used, but it is | often highly sub-optimal; however, it is also a | questionable practice for a naive management | station to attempt conceptual row creation.) | Alternately, the MIB module which defines the | conceptual row might provide one or more objects | Expires June 22, 1993 [Page 11] Draft Textual Conventions for SNMPv2 Dec 92 which provide assistance in determining an unused | instance-identifier. For example, if the | conceptual row is indexed by an integer-value, | then an object having an integer-valued SYNTAX | clause might be defined for such a purpose, | allowing a management station to issue a | management protocol retrieval operation. In order | to avoid unnecessary collisions between competing | management stations, `adjacent' retrievals of this | object should be different. | Finally, the management station could select a | pseudo-random number to use as the index. In the | event that this index was already in use and an | inconsistentValue was returned in response to the | management protocol set operation, the management | station should simply select a new pseudo-random | number and retry the operation. | A MIB designer should choose between the two | latter algorithms based on the size of the table | (and therefore the efficiency of each algorithm). | For tables in which a large number of entries are | expected, it is recommended that a MIB object be | defined that returns an acceptable index for | creation. For tables with small numbers of | entries, it is recommended that the latter | pseudo-random index mechanism be used. | Interaction 2: Creating the Conceptual Row | Once an unused instance-identifier has been | selected, the management station determines if it | wishes to create and activate the conceptual row | in one transaction or in a negotiated set of | interactions. | Interaction 2a: Creating and Activating the | Conceptual Row | The management station must first determine the | column requirements, i.e., it must determine those | columns for which it must or must not provide | values. Depending on the complexity of the table | and the management station's knowledge of the | Expires June 22, 1993 [Page 12] Draft Textual Conventions for SNMPv2 Dec 92 agent's capabilities, this determination can be | made locally by the management station. | Alternately, | the management station issues a management protocol get operation to examine all columns in | the conceptual row that it wishes to create. In | response, for each column, there are three | possible outcomes: | - a value is returned, indicating that some | other management station has already created | this conceptual row. We return to | interaction 1. | - the exception `noSuchInstance' is returned, | indicating that the agent implements the | object-type associated with this column, and | that this column in at least one conceptual | row would be accessible in the MIB view used | by the retrieval were it to exist. For those | columns to which the agent provides read- | create access, the `noSuchInstance' exception | tells the management station that it should | supply a value for this column when the | conceptual row is to be created. | - the exception `noSuchObject' is returned, | indicating that the agent does not implement | the object-type associated with this column | or that there is no conceptual row for which | this column would be accessible in the MIB | view used by the retrieval. As such, the | management station can not issue any | management protocol set operations to create | an instance of this column. | Once the column requirements have been determined, | a management protocol set operation is accordingly | issued. This operation also sets the new instance | of the status column to `createAndGo'. | When the agent processes the set operation, it | verifies that it has sufficient information to | make the conceptual row available for use by the | managed device. The information available to the | Expires June 22, 1993 [Page 13] Draft Textual Conventions for SNMPv2 Dec 92 agent is provided by two sources: the management | protocol set operation which creates the | conceptual row, | and, implementation-specific defaults supplied by | the agent (note that an agent must provide | implementation-specific defaults for at least | those objects which it implements as read-only). | If there is sufficient information available, then | the conceptual row is created, a `noError' | response is returned, the status column is set to | `active', and no further interactions are | necessary (i.e., interactions 3 and 4 are | skipped). If there is insufficient information, | then the conceptual row is not created, and the | set operation fails with an error of | `inconsistentValue'. On this error, the | management station can issue a management protocol | retrieval operation to determine if this was | because it failed to specify a value for a | required column, or, because the selected instance | of the status column already existed. In the | latter case, we return to interaction 1. In the | former case, the management station can re-issue | the set operation with the additional information, | or begin interaction 2 again using `createAndWait' | in order to negotiate creation of the conceptual | row. | Expires June 22, 1993 [Page 14] Draft Textual Conventions for SNMPv2 Dec 92 NOTE WELL | Regardless of the method used to determine | the column requirements, it is possible that | the management station might deem a column | necessary when, in fact, the agent will not | allow that particular columnar instance to be | created or written. In this case, the | management protocol set operation will fail | with an error such as `noCreation' or | `notWritable'. In this case, the management | station decides whether it needs to be able | to set a value for that particular columnar | instance. If not, the management station | re-issues the management protocol set | operation, but without setting a value for | that particular columnar instance; otherwise, | the management station aborts the row | creation algorithm. | Interaction 2b: Negotiating the Creation of the | Conceptual Row | The management station issues a management | protocol set operation which sets the desired | instance of the status column to `createAndWait'. | If the agent is unwilling to process a request of | this sort, the set operation fails with an error | of `wrongValue'. (As a consequence, such an agent | must be prepared to accept a single management | protocol set operation, i.e., interaction 2a | above, containing all of the columns indicated by | its column requirements.) Otherwise, the | conceptual row is created, a `noError' response is | returned, and the status column is immediately set | to either `notInService' or `notReady', depending | on whether it has sufficient information to make | the conceptual row available for use by the | managed device. If there is sufficient | information available, then the status column is | set to `notInService'; otherwise, if there is | insufficient information, then the status column | is set to `notReady'. Regardless, we proceed to | interaction 3. | Expires June 22, 1993 [Page 15] Draft Textual Conventions for SNMPv2 Dec 92 Interaction 3: Initializing non-defaulted Objects | The management station must now determine the | column requirements. It issues a management | protocol get operation to examine all columns in | the created conceptual row. In the response, for | each column, there are three possible outcomes: | - a value is returned, indicating that the | agent implements the object-type associated | with this column and had sufficient | information to provide a value. For those | columns to which the agent provides read- | create access, a value return tells the | management station that it may issue | additional management protocol set | operations, if it desires, in order to change | the value associated with this column. | - the exception `noSuchInstance' is returned, | indicating that the agent implements the | object-type associated with this column, and | that this column in at least one conceptual | row would be accessible in the MIB view used | by the retrieval were it to exist. | However, the agent does not have sufficient | information to provide a value, and until a | value is provided, the conceptual row may not | be made available for use by the managed | device. For those columns to which the agent | provides read-create access, the | `noSuchInstance' exception tells the | management station that it must issue | additional management protocol set | operations, in order to provide a value | associated with this column. | - the exception `noSuchObject' is returned, | indicating that the agent does not implement | the object-type associated with this column | or that there is no conceptual row for which | this column would be accessible in the MIB | view used by the retrieval. | As such, the management station can not issue | any management protocol set operations to | Expires June 22, 1993 [Page 16] Draft Textual Conventions for SNMPv2 Dec 92 create an instance of this column. | If the value associated with the status column is | `notReady', then the management station must first | deal with all `noSuchInstance' columns, if any. | Having done so, the value of the status column | becomes `notInService', and we proceed to | interaction 4. | Interaction 4: Making the Conceptual Row Available | Once the management station is satisfied with the | values associated with the columns of the | conceptual row, it issues a management protocol | set operation to set the status column to | `active'. If the agent has sufficient information | to make the conceptual row available for use by | the managed device, the management protocol set | operation succeeds (a `noError' response is | returned). Otherwise, the management protocol set | operation fails with an error of | `inconsistentValue'. | NOTE WELL | A conceptual row having a status column with | value `notInService' or `notReady' is | unavailable to the managed device. As such, | it is possible for the managed device to | create its own instances during the time | between the management protocol set operation | which sets the status column to | `createAndWait' and the management protocol | set operation which sets the status column to | `active'. In this case, when the management | protocol set operation is issued to set the | status column to `active', the values held in | the agent supersede those used by the managed | device. | If the management station is prevented from | setting the status column to `active' (e.g., due | to management station or network failure) the | conceptual row will be left in the `notInService' | or `notReady' state, consuming resources | Expires June 22, 1993 [Page 17] Draft Textual Conventions for SNMPv2 Dec 92 indefinitely. The agent must detect conceptual | rows that have been in either state for an | abnormally long period of time and remove them. | This period of time should be long enough to allow | for human response time | (including `think time') between the creation of | the conceptual row and the setting of the status | to `active'. It is suggested that this period be | approximately 5 minutes in length. | Conceptual Row Suspension | When a conceptual row is `active', the management + station may issue a management protocol set + operation which sets the instance of the status + column to `notInService'. If the agent is + unwilling to do so, the set operation fails with + an error of `wrongValue'. Otherwise, the + conceptual row is taken out of service, and a + `noError' response is returned. It is the + responsibility of the the DESCRIPTION clause of + the status column to indicate under what + circumstances the status column should be taken + out of service (e.g., in order for the value of + some other column of the same conceptual row to be + modified). + Conceptual Row Deletion + For deletion of conceptual rows, a management | protocol set operation is issued which sets the | instance of the status column to `destroy'. This | request may be made regardless of the current | value of the status column (e.g., it is possible | to delete conceptual rows which are either | `notReady', `notInService' or `active'.) | If the operation succeeds, then all instances | associated with the conceptual row are immediately | removed." | Expires June 22, 1993 [Page 18] Draft Textual Conventions for SNMPv2 Dec 92 SYNTAX INTEGER { -- the following two values are states: | -- these values may be read or written | active(1), | notInService(2), | -- the following value is a state: + -- this value may be read, but not written + notReady(3), + -- the following three values are + -- actions: these values may be written, + -- but are never read + createAndGo(4), + createAndWait(5), + destroy(6) + } + Expires June 22, 1993 [Page 19] Draft Textual Conventions for SNMPv2 Dec 92 TimeStamp ::= TEXTUAL-CONVENTION STATUS current DESCRIPTION "The value of MIB-II's sysUpTime object at which a specific occurrence happened. The specific occurrence must be defined in the description of any object defined using this type." SYNTAX TimeTicks TimeInterval ::= TEXTUAL-CONVENTION STATUS current DESCRIPTION "A period of time, measured in units of 0.01 seconds." SYNTAX INTEGER (0..2147483647) Expires June 22, 1993 [Page 20] Draft Textual Conventions for SNMPv2 Dec 92 DateAndTime ::= TEXTUAL-CONVENTION DISPLAY-HINT "2d-1d-1d,1d:1d:1d.1d,1a1d:1d" STATUS current DESCRIPTION "A date-time specification. field octets contents range ----- ------ -------- ----- 1 1-2 year 0..65536 2 3 month 1..12 3 4 day 1..31 4 5 hour 0..23 5 6 minutes 0..59 6 7 seconds 0..60 (use 60 for leap-second) 7 8 deci-seconds 0..9 8 9 direction from UTC '+' / '-' 9 10 hours from UTC 0..11 10 11 minutes from UTC 0..59 For example, Tuesday May 26, 1992 at 1:30:15 PM EDT would be displayed as: 1992-5-26,13:30:15.0,-4:0 Note that if only local time is known, then | timezone information (fields 8-10) is not | present." | SYNTAX OCTET STRING (SIZE (8 | 11)) END Expires June 22, 1993 [Page 21] Draft Textual Conventions for SNMPv2 Dec 92 3. Mapping of the TEXTUAL-CONVENTION macro The TEXTUAL-CONVENTION macro is used to convey the syntax and semantics associated with a textual convention. It should be noted that the expansion of the TEXTUAL-CONVENTION macro is something which conceptually happens during implementation and not during run-time. For all descriptors appearing in an information module, the descriptor shall be unique and mnemonic, and shall not exceed 64 characters in length. Further, the hyphen is not allowed as a character in the name of any textual convention. 3.1. Mapping of the DISPLAY-HINT clause The DISPLAY-HINT clause, which need not be present, gives a hint as to how the value of an instance of an object with the syntax defined using this textual convention might be displayed. The DISPLAY-HINT clause may only be present when the syntax has an underlying primitive type of INTEGER or OCTET STRING. When the syntax has an underlying primitive type of INTEGER, the hint consists of a single character suggesting a display format, either: `x' for hexadecimal, `d' for decimal, or `o' for octal, or `b' for binary. When the syntax has an underlying primitive type of OCTET STRING, the hint consists of one or more octet-format specifications. Each specification consists of five parts, with each part using and removing zero or more of the next octets from the value and producing the next zero or more characters to be displayed. The octets within the value are processed in order of significance, most significant first. The five parts of a octet-format specification are: (1) the (optional) repeat indicator; if present, this part is a `*', and indicates that the current octet of the value is to be used as the repeat count. The repeat count is an unsigned integer (which may be zero) which specifies how many times the remainder of this octet-format specification should be successively applied. If the repeat indicator is not present, the repeat count is one. Expires June 22, 1993 [Page 22] Draft Textual Conventions for SNMPv2 Dec 92 (2) the octet length: one or more decimal digits specifying the number of octets of the value to be used and formatted by this octet-specification. Note that the octet length can be zero. If less than this number of octets remain in the value, then the lesser number of octets are used. (3) the display format, either: `x' for hexadecimal, `d' for decimal, `o' for octal, or `a' for ascii. If the octet length part is greater than one, and the display format part refers to a numeric format, then network-byte ordering (big-endian encoding) is used interpreting the octets in the value. (4) the (optional) display separator character; if present, this part is a single character which is produced for display after each application of this octet- specification; however, this character is not produced for display if it would be immediately followed by the display of the repeat terminator character for this octet-specification. This character can be any character other than a decimal digit and a `*'. (5) the (optional) repeat terminator character, which can be present only if the display separator character is present and this octet-specification begins with a repeat indicator; if present, this part is a single character which is produced after all the zero or more repeated applications (as given by the repeat count) of this octet-specification. This character can be any character other than a decimal digit and a `*'. Output of a display separator character or a repeat terminator character is suppressed if it would occur as the last character of the display. If the octets of the value are exhausted before all the octet-format specification have been used, then the excess specifications are ignored. If additional octets remain in the value after interpreting all the octet-format specifications, then the last octet-format specification is re-interpreted to process the additional octets, until no octets remain in the value. Expires June 22, 1993 [Page 23] Draft Textual Conventions for SNMPv2 Dec 92 3.2. Mapping of the STATUS clause The STATUS clause, which must be present, indicates whether this definition is current or historic. The values "current", and "obsolete" are self-explanatory. The "deprecated" value indicates that the textual convention is obsolete, but that an implementor may wish to support that object to foster interoperability with older implementations. 3.3. Mapping of the DESCRIPTION clause The DESCRIPTION clause, which must be present, contains a textual definition of the textual convention, which provides all semantic definitions necessary for implementation, and should embody any information which would otherwise be communicated in any ASN.1 commentary annotations associated with the object. Note that, in order to conform to the ASN.1 syntax, the entire value of this clause must be enclosed in double quotation marks, and therefore cannot itself contain double quotation marks, although the value may be multi-line. 3.4. Mapping of the REFERENCE clause The REFERENCE clause, which need not be present, contains a textual cross-reference to a related item defined in some other published work. 3.5. Mapping of the SYNTAX clause The SYNTAX clause, which must be present, defines abstract data structure corresponding to the textual convention. The data structure must be one of the alternatives defined in the ObjectSyntax CHOICE [2]. Full ASN.1 sub-typing is allowed, as appropriate to the underingly ASN.1 type, primarily as an aid to implementors in understanding the meaning of the textual convention. Of course, sub-typing is not allowed for textual conventions derived from either the Counter32 or Counter64 types, but is Expires June 22, 1993 [Page 24] Draft Textual Conventions for SNMPv2 Dec 92 allowed for textual conventions derived from the Gauge32 type. Expires June 22, 1993 [Page 25] Draft Textual Conventions for SNMPv2 Dec 92 4. Acknowledgements PhysAddress (and textual conventions) originated in RFC 1213. MacAddress originated in RFCs 1230 and 1231. TruthValue originated in RFC 1253. AutonomousType and InstancePointer originated in RFC 1316. RowStatus originated in RFC 1271. A special thanks to Bancroft Scott of Open Systems Solutions, Inc., for helping in the definition of the TEXTUAL-CONVENTIONS macro. Finally, the comments of the SNMP version 2 working group are gratefully acknowledged: Beth Adams, Network Management Forum Steve Alexander, INTERACTIVE Systems Corporation David Arneson, Cabletron Systems Toshiya Asaba, Fred Baker, ACC Jim Barnes, Xylogics, Inc. Brian Bataille Andy Bierman, SynOptics Communications, Inc. Uri Blumenthal, IBM Corporation Fred Bohle, Interlink Jack Brown Theodore Brunner, Bellcore Stephen F. Bush, GE Information Services Deirdre C. Kostik, Bellcore Jeff Case, University of Tennessee, Knoxville John Chang, IBM Corporation Szusin Chen, Sun Microsystems Robert Ching Chris Chiotasso, Ungermann-Bass Bobby A. Clay, NASA/Boeing John Cooke, Chipcom Tracy Cox, Bellcore Juan Cruz, Datability, Inc. David Cullerot, Cabletron Systems Cathy Cunningham, Microcom James R. (Chuck) Davin, Bellcore Expires June 22, 1993 [Page 26] Draft Textual Conventions for SNMPv2 Dec 92 Michael Davis, Clearpoint Mike Davison, FiberCom Cynthia DellaTorre, MITRE Taso N. Devetzis, Bellcore Manual Diaz, DAVID Systems, Inc. Jon Dreyer, Sun Microsystems Susan E. Hicks, Martin Marietta Energy Systems David Engel, Optical Data Systems Mike Erlinger, Lexcel Roger Fajman, NIH Daniel Fauvarque, Sun Microsystems Karen Frisa, CMU Shari Galitzer, MITRE Shawn Gallagher, Digital Equipment Corporation Richard Graveman, Bellcore Maria Greene, Xyplex, Inc. Michel Guittet, Apple Robert Gutierrez, NASA Bill Hagerty, Cabletron Systems Gary W. Haney, Martin Marietta Energy Systems Patrick Hanil, Nokia Telecommunications Matt Hecht, SNMP Research, Inc. Edward A. Heiner, Jr., Synernetics Inc. Geral Holzhauer, Apple John Hopprich, DAVID Systems, Inc. Jeff Hughes, Hewlett-Packard Robin Iddon, Axon Networks, Inc. David Itusak Kevin M. Jackson, Concord Communications, Inc. Ole J. Jacobsen, Interop Company Ronald Jacoby, Silicon Graphics, Inc. Satish Joshi, SynOptics Communications, Inc. Frank Kastenholz, FTP Software Mark Kepke, Hewlett-Packard Ken Key, SNMP Research, Inc. Zbiginew Kielczewski, Eicon Jongyeoi Kim Andrew Knutsen, The Santa Cruz Operation Michael L Kornegay, VisiSoft Cheryl Krupczak, Georgia Tech Steven L. Waldbusser, Carnegie Mellon Universitty Mark S. Lewis, Telebit David Lin David Lindemulder, AT&T/NCR Ben Lisowski, Sprint Expires June 22, 1993 [Page 27] Draft Textual Conventions for SNMPv2 Dec 92 David Liu, Bell-Northern Research John Lunny, The Wollongong Group Robert C. Lushbaugh Martin, Marietta Energy Systems Michael Luufer, BBN Carl Madison, Star-Tek, Inc. Keith McCloghrie, Hughes LAN Systems Evan McGinnis, 3Com Corporation Bill McKenzie, IBM Corporation Donna McMaster, SynOptics Communications, Inc. John Medicke, IBM Corporation Doug Miller, Telebit Dave Minnich, FiberCom Mohammad Mirhakkak, MITRE Rohit Mital, Protools George Mouradian, AT&T Bell Labs Patrick Mullaney, Cabletron Systems Dan Myers, 3Com Corporation Rina Nathaniel, Rad Network Devices Ltd. Hien V. Nguyen, Sprint Mo Nikain Tom Nisbet William B. Norton, MERIT Steve Onishi, Wellfleet Communications, Inc. David T. Perkins, SynOptics Communications, Inc. Carl Powell, BBN Ilan Raab, SynOptics Communications, Inc. RIchard Ramons, AT&T Venkat D. Rangan, Metric Network Systems, Inc. Louise Reingold, Sprint Sam Roberts, Farallon Computing, Inc. Kary Robertson, Concord Communications, Inc. Dan Romascanu, Lannet Data Communications Ltd. Marshall T. Rose, Dover Beach Consulting, Inc. Shawn A. Routhier, Epilogue Technology Corporation Chris Rozman Asaf Rubissa, Fibronics Jon Saperia, Digital Equipment Corporation Michael Sapich Mike Scanlon, Interlan Sam Schaen, MITRE John Seligson, Ultra Network Technologies Paul A. Serice, Corporation for Open Systems Chris Shaw, Banyan Systems Timon Sloane Robert Snyder, Cisco Systems Expires June 22, 1993 [Page 28] Draft Textual Conventions for SNMPv2 Dec 92 Joo Young Song Roy Spitier, Sprint Einar Stefferud, Network Management Associates John Stephens, Cayman Systems, Inc. Bob Stewart, Xyplex, Inc. (chair) Kaj Tesink, Bellcore Dean Throop, Data General Ahmet Tuncay, France Telecom-CNET Maurice Turcotte, Racal Datacom Warren Vik, INTERACTIVE Systems Corporation Yannis Viniotis Steve Waldbusser, CMU Timothy M. Walden, ACC Alice Wang, Sun Microsystems James Watt, Newbridge Luanne Waul, Timeplex Donald E. Westlake III, Digital Equipment Corporation Gerry White Bert Wijnen, IBM Corporation Peter Wilson, 3Com Corporation Steven Wong, Digital Equipment Corporation Randy Worzella, IBM Corporation Daniel Woycke, MITRE Honda Wu Jeff Yarnell, Protools Chris Young, Cabletron Kiho Yum, 3Com Corporation Expires June 22, 1993 [Page 29] Draft Textual Conventions for SNMPv2 Dec 92 5. References [1] Information processing systems - Open Systems Interconnection - Specification of Abstract Syntax Notation One (ASN.1), International Organization for Standardization. International Standard 8824, (December, 1987). [2] J.D. Case, K. McCloghrie, M.T. Rose, S.L. Waldbusser, Structure of Management Information for version 2 of the Simple Network Management Protocol (SNMPv2). Internet- Draft, (December 22, 1992). | Expires June 22, 1993 [Page 30] Draft Textual Conventions for SNMPv2 Dec 92 Table of Contents 1 Introduction .......................................... 2 1.1 A Note on Terminology ............................... 3 2 Definitions ........................................... 4 3 Mapping of the TEXTUAL-CONVENTION macro ............... 22 3.1 Mapping of the DISPLAY-HINT clause .................. 22 3.2 Mapping of the STATUS clause ........................ 24 3.3 Mapping of the DESCRIPTION clause ................... 24 3.4 Mapping of the REFERENCE clause ..................... 24 3.5 Mapping of the SYNTAX clause ........................ 24 4 Acknowledgements ...................................... 26 5 References ............................................ 30 Expires June 22, 1993 [Page 31]