Internet DRAFT - draft-kzm-smiv2-conf
draft-kzm-smiv2-conf
HTTP/1.1 200 OK
Date: Tue, 09 Apr 2002 09:42:38 GMT
Server: Apache/1.3.20 (Unix)
Last-Modified: Fri, 14 Aug 1998 13:07:00 GMT
ETag: "324002-cb24-35d43674"
Accept-Ranges: bytes
Content-Length: 52004
Connection: close
Content-Type: text/plain
Network Working Group Keith McCloghrie
Internet Draft Cisco Systems
Juergen Schoenwaelder
TU Braunschweig
6 August 1998
Conformance Statements for SMIv2
draft-kzm-smiv2-conf-00.txt
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.ietf.org (US East Coast), nic.nordu.net (Europe),
ftp.isi.edu (US West Coast), or munnari.oz.au (Pacific Rim).
Copyright Notice
Copyright (C) The Internet Society (1998). All Rights Reserved.
Expires February 1999 [Page 1]
Draft Conformance Statements for SMIv2 August 1998
1. Introduction
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].
It may be useful to define the acceptable lower-bounds of
implementation, along with the actual level of implementation achieved.
It is the purpose of this document to define the notation used for these
purposes.
1.1. A Note on Terminology
For the purpose of exposition, the original Structure of Management
Information, as described in RFCs 1156 (STD 16), 1212 (STD 16), and RFC
1215, is termed the SMI version 1 (SMIv1). The current version of the
Structure of Management Information is termed SMI version 2 (SMIv2).
Expires February 1999 [Page 2]
Draft Conformance Statements for SMIv2 August 1998
2. Definitions
SNMPv2-CONF DEFINITIONS ::= BEGIN
IMPORTS ObjectName, NotificationName, ObjectSyntax
FROM SNMPv2-SMI;
-- definitions for conformance groups
OBJECT-GROUP MACRO ::=
BEGIN
TYPE NOTATION ::=
ObjectsPart
"STATUS" Status
"DESCRIPTION" Text
ReferPart
VALUE NOTATION ::=
value(VALUE OBJECT IDENTIFIER)
ObjectsPart ::=
"OBJECTS" "{" Objects "}"
Objects ::=
Object
| Objects "," Object
Object ::=
value(Name ObjectName)
Status ::=
"current"
| "deprecated"
| "obsolete"
ReferPart ::=
"REFERENCE" Text
| empty
-- a character string as defined in [2]
Text ::= """" string """"
END
Expires February 1999 [Page 3]
Draft Conformance Statements for SMIv2 August 1998
-- more definitions for conformance groups
NOTIFICATION-GROUP MACRO ::=
BEGIN
TYPE NOTATION ::=
NotificationsPart
"STATUS" Status
"DESCRIPTION" Text
ReferPart
VALUE NOTATION ::=
value(VALUE OBJECT IDENTIFIER)
NotificationsPart ::=
"NOTIFICATIONS" "{" Notifications "}"
Notifications ::=
Notification
| Notifications "," Notification
Notification ::=
value(Name NotificationName)
Status ::=
"current"
| "deprecated"
| "obsolete"
ReferPart ::=
"REFERENCE" Text
| empty
-- a character string as defined in [2]
Text ::= """" string """"
END
Expires February 1999 [Page 4]
Draft Conformance Statements for SMIv2 August 1998
-- definitions for compliance statements
MODULE-COMPLIANCE MACRO ::=
BEGIN
TYPE NOTATION ::=
"STATUS" Status
"DESCRIPTION" Text
ReferPart
ModulePart
VALUE NOTATION ::=
value(VALUE OBJECT IDENTIFIER)
Status ::=
"current"
| "deprecated"
| "obsolete"
ReferPart ::=
"REFERENCE" Text
| empty
ModulePart ::=
Modules
| empty
Modules ::=
Module
| Modules Module
Module ::=
-- name of module --
"MODULE" ModuleName
MandatoryPart
CompliancePart
ModuleName ::=
modulereference ModuleIdentifier
-- must not be empty unless contained
-- in MIB Module
| empty
ModuleIdentifier ::=
value(ModuleID OBJECT IDENTIFIER)
| empty
MandatoryPart ::=
"MANDATORY-GROUPS" "{" Groups "}"
Expires February 1999 [Page 5]
Draft Conformance Statements for SMIv2 August 1998
| empty
Groups ::=
Group
| Groups "," Group
Group ::=
value(Group OBJECT IDENTIFIER)
CompliancePart ::=
Compliances
| empty
Compliances ::=
Compliance
| Compliances Compliance
Compliance ::=
ComplianceGroup
| Object
ComplianceGroup ::=
"GROUP" value(Name OBJECT IDENTIFIER)
"DESCRIPTION" Text
Object ::=
"OBJECT" value(Name ObjectName)
SyntaxPart
WriteSyntaxPart
AccessPart
"DESCRIPTION" Text
-- must be a refinement for object's SYNTAX clause
SyntaxPart ::= "SYNTAX" Syntax
| empty
-- must be a refinement for object's SYNTAX clause
WriteSyntaxPart ::= "WRITE-SYNTAX" Syntax
| empty
Syntax ::= type(ObjectSyntax)
| "BITS" "{" NamedBits "}"
NamedBits ::= NamedBit
| NamedBits "," NamedBit
NamedBit ::= identifier "(" number ")" -- number is nonnegative
Expires February 1999 [Page 6]
Draft Conformance Statements for SMIv2 August 1998
AccessPart ::=
"MIN-ACCESS" Access
| empty
Access ::=
"not-accessible"
| "accessible-for-notify"
| "read-only"
| "read-write"
| "read-create"
-- a character string as defined in [2]
Text ::= """" string """"
END
Expires February 1999 [Page 7]
Draft Conformance Statements for SMIv2 August 1998
-- definitions for capabilities statements
AGENT-CAPABILITIES MACRO ::=
BEGIN
TYPE NOTATION ::=
"PRODUCT-RELEASE" Text
"STATUS" Status
"DESCRIPTION" Text
ReferPart
ModulePart
VALUE NOTATION ::=
value(VALUE OBJECT IDENTIFIER)
Status ::=
"current"
| "obsolete"
ReferPart ::=
"REFERENCE" Text
| empty
ModulePart ::=
Modules
| empty
Modules ::=
Module
| Modules Module
Module ::=
-- name of module --
"SUPPORTS" ModuleName
"INCLUDES" "{" Groups "}"
VariationPart
ModuleName ::=
identifier ModuleIdentifier
ModuleIdentifier ::=
value(ModuleID OBJECT IDENTIFIER)
| empty
Groups ::=
Group
| Groups "," Group
Group ::=
value(Name OBJECT IDENTIFIER)
Expires February 1999 [Page 8]
Draft Conformance Statements for SMIv2 August 1998
VariationPart ::=
Variations
| empty
Variations ::=
Variation
| Variations Variation
Variation ::=
ObjectVariation
| NotificationVariation
NotificationVariation ::=
"VARIATION" value(Name NotificationName)
AccessPart
"DESCRIPTION" Text
ObjectVariation ::=
"VARIATION" value(Name ObjectName)
SyntaxPart
WriteSyntaxPart
AccessPart
CreationPart
DefValPart
"DESCRIPTION" Text
-- must be a refinement for object's SYNTAX clause
SyntaxPart ::= "SYNTAX" Syntax
| empty
WriteSyntaxPart ::= "WRITE-SYNTAX" Syntax
| empty
Syntax ::= type(ObjectSyntax)
| "BITS" "{" NamedBits "}"
NamedBits ::= NamedBit
| NamedBits "," NamedBit
NamedBit ::= identifier "(" number ")" -- number is nonnegative
AccessPart ::=
"ACCESS" Access
| empty
Access ::=
Expires February 1999 [Page 9]
Draft Conformance Statements for SMIv2 August 1998
"not-implemented"
-- only "not-implemented" for notifications
| "accessible-for-notify"
| "read-only"
| "read-write"
| "read-create"
-- following is for backward-compatibility only
| "write-only"
CreationPart ::=
"CREATION-REQUIRES" "{" Cells "}"
| empty
Cells ::=
Cell
| Cells "," Cell
Cell ::=
value(Cell ObjectName)
DefValPart ::= "DEFVAL" "{" Value "}"
| empty
Value ::= value(Defval ObjectSyntax)
| "{" BitsValue "}"
BitsValue ::= BitNames
| empty
BitNames ::= BitName
| BitNames "," BitName
BitName ::= identifier
-- a character string as defined in [2]
Text ::= """" string """"
END
END
Expires February 1999 [Page 10]
Draft Conformance Statements for SMIv2 August 1998
3. Mapping of the OBJECT-GROUP macro
For conformance purposes, it is useful to define a collection of related
managed objects. The OBJECT-GROUP macro is used to define each such
collection of related objects. It should be noted that the expansion of
the OBJECT-GROUP macro is something which conceptually happens during
implementation and not during run-time.
To "implement" an object, an agent must return a reasonably accurate
value for management protocol retrieval operations; similarly, if the
object is writable, then in response to a management protocol set
operation, an agent must accordingly be able to reasonably influence the
underlying managed entity. If an agent agent can not implement an
object, the management protocol provides for it to return an exception
or error, e.g, noSuchObject [4]. Under no circumstances shall an agent
return a value for objects which it does not implement -- it must always
return the appropriate exception or error, as described in the protocol
specification [4].
3.1. Mapping of the OBJECTS clause
The OBJECTS clause, which must be present, is used to name each object
contained in the conformance group. Each of the named objects must be
defined in the same information module as the OBJECT-GROUP macro
appears, and must have a MAX-ACCESS clause value of "accessible-for-
notify", "read-only", "read-write", or "read-create".
It is required that every object defined in an information module with a
MAX-ACCESS clause other than "not-accessible" be contained in at least
one object group. This avoids the common error of adding a new object
to an information module and forgetting to add the new object to a
group.
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" means that the definition is current and valid.
The value "obsolete" means the definition is obsolete and should not be
implemented and/or can be removed if previously implemented. While the
value "deprecated" also indicates an obsolete definition, it permits
new/continued implementation in order to foster interoperability with
Expires February 1999 [Page 11]
Draft Conformance Statements for SMIv2 August 1998
older/existing implementations.
3.3. Mapping of the DESCRIPTION clause
The DESCRIPTION clause, which must be present, contains a textual
definition of that group, along with a description of any relations to
other groups. Note that generic compliance requirements should not be
stated in this clause. However, implementation relationships between
this group and other groups may be defined in this clause.
3.4. Mapping of the REFERENCE clause
The REFERENCE clause, which need not be present, contains a textual
cross-reference to some other document, either another information
module which defines a related assignment, or some other document which
provides additional information relevant to this definition.
3.5. Mapping of the OBJECT-GROUP value
The value of an invocation of the OBJECT-GROUP macro is the name of the
group, which is an OBJECT IDENTIFIER, an administratively assigned name.
3.6. Usage Example
The SNMP Group [3] is described:
Expires February 1999 [Page 12]
Draft Conformance Statements for SMIv2 August 1998
snmpGroup OBJECT-GROUP
OBJECTS { snmpInPkts,
snmpInBadVersions,
snmpInASNParseErrs,
snmpBadOperations,
snmpSilentDrops,
snmpProxyDrops,
snmpEnableAuthenTraps }
STATUS current
DESCRIPTION
"A collection of objects providing basic instrumentation and
control of an agent."
::= { snmpMIBGroups 8 }
According to this invocation, the conformance group named
{ snmpMIBGroups 8 }
contains 7 objects.
Expires February 1999 [Page 13]
Draft Conformance Statements for SMIv2 August 1998
4. Mapping of the NOTIFICATION-GROUP macro
For conformance purposes, it is useful to define a collection of
notifications. The NOTIFICATION-GROUP macro serves this purpose. It
should be noted that the expansion of the NOTIFICATION-GROUP macro is
something which conceptually happens during implementation and not
during run-time.
4.1. Mapping of the NOTIFICATIONS clause
The NOTIFICATIONS clause, which must be present, is used to name each
notification contained in the conformance group. Each of the named
notifications must be defined in the same information module as the
NOTIFICATION-GROUP macro appears.
It is required that every notification defined in an information module
be contained in at least one notification group.
4.2. Mapping of the STATUS clause
The STATUS clause, which must be present, indicates whether this
definition is current or historic.
The values "current" means that the definition is current and valid.
The value "obsolete" means the definition is obsolete and should not be
implemented and/or can be removed if previously implemented. While the
value "deprecated" also indicates an obsolete definition, it permits
new/continued implementation in order to foster interoperability with
older/existing implementations.
4.3. Mapping of the DESCRIPTION clause
The DESCRIPTION clause, which must be present, contains a textual
definition of the group, along with a description of any relations to
other groups. Note that generic compliance requirements should not be
stated in this clause. However, implementation relationships between
this group and other groups may be defined in this clause.
Expires February 1999 [Page 14]
Draft Conformance Statements for SMIv2 August 1998
4.4. Mapping of the REFERENCE clause
The REFERENCE clause, which need not be present, contains a textual
cross-reference to some other document, either another information
module which defines a related assignment, or some other document which
provides additional information relevant to this definition.
4.5. Mapping of the NOTIFICATION-GROUP value
The value of an invocation of the NOTIFICATION-GROUP macro is the name
of the group, which is an OBJECT IDENTIFIER, an administratively
assigned name.
4.6. Usage Example
The SNMP Basic Notifications Group [3] is described:
snmpBasicNotificationsGroup NOTIFICATION-GROUP
NOTIFICATIONS { coldStart, authenticationFailure }
STATUS current
DESCRIPTION
"The two notifications which an agent is required to
implement."
::= { snmpMIBGroups 7 }
According to this invocation, the conformance group named
{ snmpMIBGroups 7 }
contains 2 notifications.
Expires February 1999 [Page 15]
Draft Conformance Statements for SMIv2 August 1998
5. Mapping of the MODULE-COMPLIANCE macro
The MODULE-COMPLIANCE macro is used to convey a minimum set of
requirements with respect to implementation of one or more MIB modules.
It should be noted that the expansion of the MODULE-COMPLIANCE macro is
something which conceptually happens during implementation and not
during run-time.
A requirement on all "standard" MIB modules is that a corresponding
MODULE-COMPLIANCE specification is also defined, either in the same
information module or in a companion information module.
5.1. Mapping of the STATUS clause
The STATUS clause, which must be present, indicates whether this
definition is current or historic.
The values "current" means that the definition is current and valid.
The value "obsolete" means the definition is obsolete and should not be
implemented and/or can be removed if previously implemented. While the
value "deprecated" also indicates an obsolete definition, it permits
new/continued implementation in order to foster interoperability with
older/existing implementations.
5.2. Mapping of the DESCRIPTION clause
The DESCRIPTION clause, which must be present, contains a textual
definition of this compliance statement and should embody any
information which would otherwise be communicated in any ASN.1
commentary annotations associated with the statement.
5.3. Mapping of the REFERENCE clause
The REFERENCE clause, which need not be present, contains a textual
cross-reference to some other document, either another information
module which defines a related assignment, or some other document which
provides additional information relevant to this definition.
Expires February 1999 [Page 16]
Draft Conformance Statements for SMIv2 August 1998
5.4. Mapping of the MODULE clause
The MODULE clause, which must be present, is repeatedly used to name
each MIB module for which compliance requirements are being specified.
Each MIB module is named by its module name, and optionally, by its
associated OBJECT IDENTIFIER as well. The module name can be omitted
when the MODULE-COMPLIANCE invocation occurs inside a MIB module, to
refer to the encompassing MIB module.
5.4.1. Mapping of the MANDATORY-GROUPS clause
The MANDATORY-GROUPS clause, which need not be present, names the one or
more object or notification groups within the correspondent MIB module
which are unconditionally mandatory for implementation. If an agent
claims compliance to the MIB module, then it must implement each and
every object and notification within each conformance group listed.
That is, if an agent returns a noSuchObject exception in response to a
management protocol get operation [4] for any object within any
mandatory conformance group for every MIB view, or if the agent cannot
generate each notification listed in any conformance group under the
appropriate circumstances, then that agent is not a conformant
implementation of the MIB module.
5.4.2. Mapping of the GROUP clause
The GROUP clause, which need not be present, is repeatedly used to name
each object and notification group which is conditionally mandatory or
unconditionally optional for compliance to the MIB module. A group
named in a GROUP clause must be absent from the correspondent
MANDATORY-GROUPS clause.
Conditionally mandatory groups include those which are mandatory only if
a particular protocol is implemented, or only if another group is
implemented. A GROUP clause's DESCRIPTION specifies the conditions
under which the group is conditionally mandatory.
A group which is named in neither a MANDATORY-GROUPS clause nor a GROUP
clause, is unconditionally optional for compliance to the MIB module.
Expires February 1999 [Page 17]
Draft Conformance Statements for SMIv2 August 1998
5.4.3. Mapping of the OBJECT clause
The OBJECT clause, which need not be present, is repeatedly used to name
each MIB object for which compliance has a refined requirement with
respect to the MIB module definition. The MIB object must be present in
one of the conformance groups named in the correspondent MANDATORY-
GROUPS clause or GROUP clauses.
By definition, each object specified in an OBJECT clause follows a
MODULE clause which names the information module in which that object is
defined. Therefore, the use of an IMPORTS statement, to specify from
where such objects are imported, is redundant and is not required in an
information module.
5.4.3.1. Mapping of the SYNTAX clause
The SYNTAX clause, which need not be present, is used to provide a
refined SYNTAX for the object named in the correspondent OBJECT clause.
Note that if this clause and a WRITE-SYNTAX clause are both present,
then this clause only applies when instances of the object named in the
correspondent OBJECT clause are read.
Consult Section 9 of [2] for more information on refined syntax.
5.4.3.2. Mapping of the WRITE-SYNTAX clause
The WRITE-SYNTAX clause, which need not be present, is used to provide a
refined SYNTAX for the object named in the correspondent OBJECT clause
when instances of that object are written.
Consult Section 9 of [2] for more information on refined syntax.
5.4.3.3. Mapping of the MIN-ACCESS clause
The MIN-ACCESS clause, which need not be present, is used to define the
minimal level of access for the object named in the correspondent OBJECT
clause. If this clause is absent, the minimal level of access is the
same as the maximal level specified in the correspondent invocation of
the OBJECT-TYPE macro. If present, this clause must not specify a
greater level of access than is specified in the correspondent
invocation of the OBJECT-TYPE macro.
Expires February 1999 [Page 18]
Draft Conformance Statements for SMIv2 August 1998
The level of access for certain types of objects is fixed according to
their syntax definition. These types include: conceptual tables and
rows, auxiliary objects, and objects with the syntax of Counter32,
Counter64 (and possibly, certain types of textual conventions). A MIN-
ACCESS clause should not be present for such objects.
An implementation is compliant if the level of access it provides is
greater or equal to the minimal level in the MODULE-COMPLIANCE macro and
less or equal to the maximal level in the OBJECT-TYPE macro.
5.4.4. Mapping of the DESCRIPTION clause
The DESCRIPTION clause must be present for each use of the GROUP or
OBJECT clause. For an OBJECT clause, it contains a textual description
of the refined compliance requirement. For a GROUP clause, it contains
a textual description of the conditions under which the group is
conditionally mandatory or unconditionally optional.
5.5. Mapping of the MODULE-COMPLIANCE value
The value of an invocation of the MODULE-COMPLIANCE macro is an OBJECT
IDENTIFIER. As such, this value may be authoritatively used when
referring to the compliance statement embodied by that invocation of the
macro.
Expires February 1999 [Page 19]
Draft Conformance Statements for SMIv2 August 1998
5.6. Usage Example
The compliance statement contained in the (hypothetical) XYZv2-MIB might
be:
xyzMIBCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for XYZv2 entities which implement
the XYZv2 MIB."
MODULE -- compliance to the containing MIB module
MANDATORY-GROUPS { xyzSystemGroup,
xyzStatsGroup, xyzTrapGroup,
xyzSetGroup,
xyzBasicNotificationsGroup }
GROUP xyzV1Group
DESCRIPTION
"The xyzV1 group is mandatory only for those
XYZv2 entities which also implement XYZv1."
::= { xyzMIBCompliances 1 }
According to this invocation, to claim alignment with the compliance
statement named
{ xyzMIBCompliances 1 }
a system must implement the XYZv2-MIB's xyzSystemGroup, xyzStatsGroup,
xyzTrapGroup, and xyzSetGroup object conformance groups, as well as the
xyzBasicNotificationsGroup notifications group. Furthermore, if the
XYZv2 entity also implements XYZv1, then it must also support the
XYZv1Group group, if compliance is to be claimed.
Expires February 1999 [Page 20]
Draft Conformance Statements for SMIv2 August 1998
6. Mapping of the AGENT-CAPABILITIES macro
The AGENT-CAPABILITIES macro is used to convey a set of capabilities
present in an agent. It should be noted that the expansion of the
AGENT-CAPABILITIES macro is something which conceptually happens during
implementation and not during run-time.
When a MIB module is written, it is divided into units of conformance
termed groups. If an agent claims to implement a group, then it must
implement each and every object within that group. Of course, for
whatever reason, an agent might implement only a subset of the groups
within a MIB module. In addition, the definition of some MIB objects
leave some aspects of the definition to the discretion of an
implementor.
Practical experience has demonstrated a need for concisely describing
the capabilities of an agent with respect to one or more MIB modules.
The AGENT-CAPABILITIES macro allows an agent implementor to describe the
precise level of support which an agent claims in regards to a MIB
group, and to bind that description to the value of an instance of
sysORID [3]. In particular, some objects may have restricted or
augmented syntax or access-levels.
If the AGENT-CAPABILITIES invocation is given to a management-station
implementor, then that implementor can build management applications
which optimize themselves when communicating with a particular agent.
For example, the management-station can maintain a database of these
invocations. When a management-station interacts with an agent, it
retrieves from the agent the values of all instances of sysORID [3].
Based on this, it consults the database to locate each entry matching
one of the retrieved values of sysORID. Using the located entries, the
management application can now optimize its behavior accordingly.
Note that the AGENT-CAPABILITIES macro specifies refinements or
variations with respect to OBJECT-TYPE and NOTIFICATION-TYPE macros in
MIB modules, NOT with respect to MODULE-COMPLIANCE macros in compliance
statements.
6.1. Mapping of the PRODUCT-RELEASE clause
The PRODUCT-RELEASE clause, which must be present, contains a textual
description of the product release which includes this set of
capabilities.
Expires February 1999 [Page 21]
Draft Conformance Statements for SMIv2 August 1998
6.2. Mapping of the STATUS clause
The STATUS clause, which must be present, indicates whether this
definition is current ("current") or historic ("obsolete").
6.3. Mapping of the DESCRIPTION clause
The DESCRIPTION clause, which must be present, contains a textual
description of this set of capabilities.
6.4. Mapping of the REFERENCE clause
The REFERENCE clause, which need not be present, contains a textual
cross-reference to some other document, either another information
module which defines a related assignment, or some other document which
provides additional information relevant to this definition.
6.5. Mapping of the SUPPORTS clause
The SUPPORTS clause, which need not be present, is repeatedly used to
name each MIB module for which the agent claims a complete or partial
implementation. Each MIB module is named by its module name, and
optionally, by its associated OBJECT IDENTIFIER (as regsitered by the
MODULE-IDENTITY macro, see [2]) as well.
6.5.1. Mapping of the INCLUDES clause
The INCLUDES clause, which must be present for each use of the SUPPORTS
clause, is used to name each MIB group associated with the SUPPORTS
clause, which the agent claims to implement.
6.5.2. Mapping of the VARIATION clause
The VARIATION clause, which need not be present, is repeatedly used to
name each object or notification which the agent implements in some
variant or refined fashion with respect to the correspondent invocation
of the OBJECT-TYPE or NOTIFICATION-TYPE macro.
Note that the variation concept is meant for generic implementation
restrictions, e.g., if the variation for an object depends on the values
Expires February 1999 [Page 22]
Draft Conformance Statements for SMIv2 August 1998
of other objects, then this should be noted in the appropriate
DESCRIPTION clause.
By definition, each object specified in a VARIATION clause follows a
SUPPORTS clause which names the information module in which that object
is defined. Therefore, the use of an IMPORTS statement, to specify from
where such objects are imported, is redundant and is not required in an
information module.
6.5.2.1. Mapping of the SYNTAX clause
The SYNTAX clause, which need not be present, is used to provide a
refined SYNTAX for the object named in the correspondent VARIATION
clause. Note that if this clause and a WRITE-SYNTAX clause are both
present, then this clause only applies when instances of the object
named in the correspondent VARIATION clause are read.
Consult Section 9 of [2] for more information on refined syntax.
6.5.2.2. Mapping of the WRITE-SYNTAX clause
The WRITE-SYNTAX clause, which need not be present, is used to provide a
refined SYNTAX for the object named in the correspondent VARIATION
clause when instances of that object are written.
Consult Section 9 of [2] for more information on refined syntax.
6.5.2.3. Mapping of the ACCESS clause
The ACCESS clause, which need not be present, is used to indicate the
agent provides less than the maximal level of access to the object or
notification named in the correspondent VARIATION clause.
The only value applicable to notifications is "not-implemented".
The value "not-implemented" indicates the agent does not implement the
object or notification, and in the ordering of possible values is
equivalent to "not-accessible".
The value "write-only" is provided solely for backward compatibility,
and shall not be used for newly-defined object types. In the ordering
of possible values, "write-only" is less than "not-accessible".
Expires February 1999 [Page 23]
Draft Conformance Statements for SMIv2 August 1998
6.5.2.4. Mapping of the CREATION-REQUIRES clause
The CREATION-REQUIRES clause, which need not be present, is used to name
the columnar objects of a conceptual row to which values must be
explicitly assigned, by a management protocol set operation, before the
agent will allow the instance of the status column of that row to be set
to `active'. (Consult the definition of RowStatus [5].)
If the conceptual row does not have a status column (i.e., the objects
corresponding to the conceptual table were defined using the mechanisms
in [6,7]), then the CREATION-REQUIRES clause, which need not be present,
is used to name the columnar objects of a conceptual row to which values
must be explicitly assigned, by a management protocol set operation,
before the agent will create new instances of objects in that row.
This clause must not be present unless the object named in the
correspondent VARIATION clause is a conceptual row, i.e., has a syntax
which resolves to a SEQUENCE containing columnar objects. The objects
named in the value of this clause usually will refer to columnar objects
in that row. However, objects unrelated to the conceptual row may also
be specified.
All objects which are named in the CREATION-REQUIRES clause for a
conceptual row, and which are columnar objects of that row, must have an
access level of "read-create".
6.5.2.5. Mapping of the DEFVAL clause
The DEFVAL clause, which need not be present, is used to provide a
refined DEFVAL value for the object named in the correspondent VARIATION
clause. The semantics of this value are identical to those of the
OBJECT-TYPE macro's DEFVAL clause.
6.5.2.6. Mapping of the DESCRIPTION clause
The DESCRIPTION clause, which must be present for each use of the
VARIATION clause, contains a textual description of the variant or
refined implementation of the object or notification.
Expires February 1999 [Page 24]
Draft Conformance Statements for SMIv2 August 1998
6.6. Mapping of the AGENT-CAPABILITIES value
The value of an invocation of the AGENT-CAPABILITIES macro is an OBJECT
IDENTIFIER, which names the value of sysORID [3] for which this
capabilities statement is valid.
6.7. Usage Example
Consider how a capabilities statement for an agent might be described:
exampleAgent AGENT-CAPABILITIES
PRODUCT-RELEASE "ACME Agent release 1.1 for 4BSD"
STATUS current
DESCRIPTION "ACME agent for 4BSD"
SUPPORTS SNMPv2-MIB
INCLUDES { systemGroup, snmpGroup, snmpSetGroup,
snmpBasicNotificationsGroup }
VARIATION coldStart
DESCRIPTION "A coldStart trap is generated on all
reboots."
SUPPORTS IF-MIB
INCLUDES { ifGeneralGroup, ifPacketGroup }
VARIATION ifAdminStatus
SYNTAX INTEGER { up(1), down(2) }
DESCRIPTION "Unable to set test mode on 4BSD"
VARIATION ifOperStatus
SYNTAX INTEGER { up(1), down(2) }
DESCRIPTION "Information limited on 4BSD"
SUPPORTS IP-MIB
INCLUDES { ipGroup, icmpGroup }
VARIATION ipDefaultTTL
SYNTAX INTEGER (255..255)
DESCRIPTION "Hard-wired on 4BSD"
VARIATION ipInAddrErrors
ACCESS not-implemented
DESCRIPTION "Information not available on 4BSD"
Expires February 1999 [Page 25]
Draft Conformance Statements for SMIv2 August 1998
VARIATION ipNetToMediaEntry
CREATION-REQUIRES { ipNetToMediaPhysAddress }
DESCRIPTION "Address mappings on 4BSD require
both protocol and media addresses"
SUPPORTS TCP-MIB
INCLUDES { tcpGroup }
VARIATION tcpConnState
ACCESS read-only
DESCRIPTION "Unable to set this on 4BSD"
SUPPORTS UDP-MIB
INCLUDES { udpGroup }
SUPPORTS EVAL-MIB
INCLUDES { functionsGroup, expressionsGroup }
VARIATION exprEntry
CREATION-REQUIRES { evalString }
DESCRIPTION "Conceptual row creation supported"
::= { acmeAgents 1 }
According to this invocation, an agent with a sysORID value of
{ acmeAgents 1 }
supports six MIB modules.
>From SNMPv2-MIB, five conformance groups are supported.
>From IF-MIB, the ifGeneralGroup and ifPacketGroup groups are supported.
However, the objects ifAdminStatus and ifOperStatus have a restricted
syntax.
>From IP-MIB, all objects in the ipGroup and icmpGroup are supported
except ipInAddrErrors, while ipDefaultTTL has a restricted range, and
when creating a new instance in the ipNetToMediaTable, the set-request
must create an instance of atPhysAddress.
>From TCP-MIB, the tcpGroup is supported except that tcpConnState is
available only for reading.
>From UDP-MIB, the udpGroup is fully supported.
Expires February 1999 [Page 26]
Draft Conformance Statements for SMIv2 August 1998
>From the EVAL-MIB, all the objects contained in the functionsGroup and
expressionsGroup conformance groups are supported, without variation.
In addition, creation of new instances in the expr table is supported.
Expires February 1999 [Page 27]
Draft Conformance Statements for SMIv2 August 1998
7. Extending an Information Module
As experience is gained with a published information module, it may be
desirable to revise that information module.
Section 10 of [2] defines the rules for extending an information module.
The remainder of this section defines how conformance groups, compliance
statements, and capabilities statements may be extended.
7.1. Conformance Groups
It may be desirable to revise the definition of a conformance group (an
OBJECT-GROUP or a NOTIFICATION-GROUP) after experience is gained with
it. However, conformance groups can be referenced by compliance and/or
capabilities definitions. Therefore, a change to a conformance group is
not allowed if it has the potential to cause a reference to the group's
original definition to be different from a reference to the updated
definition. Such changes can only be accommodated by defining a new
conformance group with a new descriptor and a new OBJECT IDENTIFIER
value.
The following revisions are allowed:
(1) A STATUS clause value of "current" may be revised as "deprecated"
or "obsolete". Similarly, a STATUS clause value of "deprecated"
may be revised as "obsolete". When making such a change, the
DESCRIPTION clause should be updated accordingly.
(2) A REFERENCE clause may be added or updated.
(3) Clarifications and additional information may be included in the
DESCRIPTION clause.
(4) Any editorial change.
It is not necessary to change the STATUS value of a conformance group
when the status of a member of the group is changed.
7.2. Compliance Definitions
It may be desirable to revise the definition of a compliance definition
(MODULE-COMPLIANCE) after experience is gained with it. However,
changes are not allowed if they cause the requirements specified by the
Expires February 1999 [Page 28]
Draft Conformance Statements for SMIv2 August 1998
original definition to be different from the requirements of the updated
definition. Such changes can only be accomodated by defining a new
compliance definition with a new descriptor and a new OBJECT IDENTIFIER
value.
The following revisions are allowed:
(1) A STATUS clause value of "current" may be revised as "deprecated"
or "obsolete". Similarly, a STATUS clause value of "deprecated"
may be revised as "obsolete". When making such a change, the
DESCRIPTION clause should be updated accordingly.
(2) A REFERENCE clause may be added or updated.
(3) Clarifications and additional information may be included in the
DESCRIPTION clause(s).
(4) Any editorial change.
It is not necessary to change the STATUS value of a compliance
definition due to a change in the STATUS value of a definition it
references.
7.3. Capabilities Definitions
It may be desirable to revise the definition of a capabilities
definition (AGENT-CAPABILITIES) after experience is gained with it.
However, changes are not allowed if they cause the capabilities
specified by the original specification to be different from the
capabilities of the updated specification. Such changes can only be
accomodated by defining a new capabilities definition with a new
descriptor and a new OBJECT IDENTIFIER value.
The following revisions are allowed:
(1) A STATUS clause value of "current" may be revised as "obsolete".
When making such a change, the DESCRIPTION clause should be updated
accordingly.
(2) A REFERENCE clause may be added or updated.
(3) Clarifications and additional information may be included in the
DESCRIPTION clause(s).
Expires February 1999 [Page 29]
Draft Conformance Statements for SMIv2 August 1998
(4) Any editorial change.
It is not necessary to change the STATUS value of a capabilities
definition due to a change in the STATUS value of a definition it
references.
Expires February 1999 [Page 30]
Draft Conformance Statements for SMIv2 August 1998
8. Security Considerations
This document defines the means to define conformance requirements for
implementing on documents describing management information. This
method of defining conformance requirements has no security impact on
the Internet.
9. Editor's Address
Keith McCloghrie
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-1706
US
Phone: +1 408 526 5260
Email: kzm@cisco.com
10. Acknowledgements
This document is the latest evolution of significant previous work by
the four major contributors:
Jeffrey D. Case (SNMP Research, case@snmp.com)
Keith McCloghrie (Cisco Systems, kzm@cisco.com)
Marshall T. Rose (First Virtual Holdings, mrose@dbc.mtview.ca.us)
Steven Waldbusser (International Network Services, stevew@uni.ins.com)
Expires February 1999 [Page 31]
Draft Conformance Statements for SMIv2 August 1998
11. 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] McCloghrie, K., and Schoenwaelder, J., "Structure of Management
Information Version 2 (SMIv2)", draft-kzm-smiv2-smi-00.txt August
1998.
[3] The SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M., and
Waldbusser, S., "Management Information Base for Version 2 of the
Simple Network Management Protocol (SNMPv2)", RFC 1907, January
1996.
[4] The SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M., and
Waldbusser, S., "Protocol Operations for Version 2 of the Simple
Network Management Protocol (SNMPv2)", RFC 1905, January 1996.
[5] McCloghrie, K., and Schoenwaelder, J., "Textual Conventions for
SMIv2", draft-kzm-smiv2-tc-00.txt August 1998.
[6] Rose, M., and McCloghrie, K., "Structure and Identification of
Management Information for TCP/IP-based internets", STD 16, RFC
1155, May 1990.
[7] Rose, M., and McCloghrie, K., "Concise MIB Definitions", STD 16,
RFC 1212, March 1991.
Expires February 1999 [Page 32]
Draft Conformance Statements for SMIv2 August 1998
12. Full Copyright Statement
Copyright (C) The Internet Society (1998). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it or
assist in its implementation may be prepared, copied, published and
distributed, in whole or in part, without restriction of any kind,
provided that the above copyright notice and this paragraph are included
on all such copies and derivative works. However, this document itself
may not be modified in any way, such as by removing the copyright notice
or references to the Internet Society or other Internet organizations,
except as needed for the purpose of developing Internet standards in
which case the procedures for copyrights defined in the Internet
Standards process must be followed, or as required to translate it into
languages other than English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an "AS
IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK
FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT
LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT
INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE."
Expires February 1999 [Page 33]
Draft Conformance Statements for SMIv2 August 1998
Table of Contents
1 Introduction .................................................... 2
1.1 A Note on Terminology ......................................... 2
2 Definitions ..................................................... 3
2.1 The OBJECT-GROUP macro ........................................ 3
2.2 The NOTIFICATION-GROUP macro .................................. 4
2.3 The MODULE-COMPLIANCE macro ................................... 5
2.4 The AGENT-CAPABILITIES macro .................................. 8
3 Mapping of the OBJECT-GROUP macro ............................... 11
3.1 Mapping of the OBJECTS clause ................................. 11
3.2 Mapping of the STATUS clause .................................. 11
3.3 Mapping of the DESCRIPTION clause ............................. 12
3.4 Mapping of the REFERENCE clause ............................... 12
3.5 Mapping of the OBJECT-GROUP value ............................. 12
3.6 Usage Example ................................................. 12
4 Mapping of the NOTIFICATION-GROUP macro ......................... 14
4.1 Mapping of the NOTIFICATIONS clause ........................... 14
4.2 Mapping of the STATUS clause .................................. 14
4.3 Mapping of the DESCRIPTION clause ............................. 14
4.4 Mapping of the REFERENCE clause ............................... 15
4.5 Mapping of the NOTIFICATION-GROUP value ....................... 15
4.6 Usage Example ................................................. 15
5 Mapping of the MODULE-COMPLIANCE macro .......................... 16
5.1 Mapping of the STATUS clause .................................. 16
5.2 Mapping of the DESCRIPTION clause ............................. 16
5.3 Mapping of the REFERENCE clause ............................... 16
5.4 Mapping of the MODULE clause .................................. 17
5.4.1 Mapping of the MANDATORY-GROUPS clause ...................... 17
5.4.2 Mapping of the GROUP clause ................................. 17
5.4.3 Mapping of the OBJECT clause ................................ 18
5.4.3.1 Mapping of the SYNTAX clause .............................. 18
5.4.3.2 Mapping of the WRITE-SYNTAX clause ........................ 18
5.4.3.3 Mapping of the MIN-ACCESS clause .......................... 18
5.4.4 Mapping of the DESCRIPTION clause ........................... 19
5.5 Mapping of the MODULE-COMPLIANCE value ........................ 19
5.6 Usage Example ................................................. 20
6 Mapping of the AGENT-CAPABILITIES macro ......................... 21
6.1 Mapping of the PRODUCT-RELEASE clause ......................... 21
6.2 Mapping of the STATUS clause .................................. 22
6.3 Mapping of the DESCRIPTION clause ............................. 22
6.4 Mapping of the REFERENCE clause ............................... 22
6.5 Mapping of the SUPPORTS clause ................................ 22
6.5.1 Mapping of the INCLUDES clause .............................. 22
Expires February 1999 [Page 34]
Draft Conformance Statements for SMIv2 August 1998
6.5.2 Mapping of the VARIATION clause ............................. 22
6.5.2.1 Mapping of the SYNTAX clause .............................. 23
6.5.2.2 Mapping of the WRITE-SYNTAX clause ........................ 23
6.5.2.3 Mapping of the ACCESS clause .............................. 23
6.5.2.4 Mapping of the CREATION-REQUIRES clause ................... 24
6.5.2.5 Mapping of the DEFVAL clause .............................. 24
6.5.2.6 Mapping of the DESCRIPTION clause ......................... 24
6.6 Mapping of the AGENT-CAPABILITIES value ....................... 25
6.7 Usage Example ................................................. 25
7 Extending an Information Module ................................. 28
7.1 Conformance Groups ............................................ 28
7.2 Compliance Definitions ........................................ 28
7.3 Capabilities Definitions ...................................... 29
8 Security Considerations ......................................... 31
9 Editor's Address ................................................ 31
10 Acknowledgements ............................................... 31
11 References ..................................................... 32
12 Full Copyright Statement ....................................... 33
Expires February 1999 [Page 35]
