RFC1749
Network Working Group K. McCloghrie Request for Comments: 1749 F. Baker Updates: 1748 E. Decker Category: Standards Track cisco Systems, Inc.
December 1994
IEEE 802.5 Station Source Routing MIB using SMIv2
Status of this Memo
This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.
Contents
Introduction
This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes managed objects used by IEEE 802.5 end- stations for managing source routes on a Token Ring network where IEEE source-routing is in use. IEEE source-routing is described in 802.5 Token Ring Access Method and Physical Layer Specifications [8] and related ISO publications [9, 10, 11].
This memo is an incremental update to RFC 1748 [6]. It is documented separately from the RFC 1748 solely due to the latter's maturity within the Internet standardization process.
The SNMPv2 Network Management Framework
The SNMPv2 Network Management Framework consists of four major components. They are:
o RFC 1442 [1] which defines the SMI, the mechanisms used for describing and naming objects for the purpose of management.
o STD 17, RFC 1213 [2] defines MIB-II, the core set of managed objects for the Internet suite of protocols.
o RFC 1445 [3] which defines the administrative and other architectural aspects of the framework.
o RFC 1448 [4] which defines the protocol used for network access to managed objects.
The Framework permits new objects to be defined for the purpose of experimentation and evaluation.
Object Definitions
Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. Objects in the MIB are defined using the subset of Abstract Syntax Notation One (ASN.1) defined in the SMI. In particular, each object type is named by an OBJECT IDENTIFIER, an administratively assigned name. The object type together with an object instance serves to uniquely identify a specific instantiation of the object. For human convenience, we often use a textual string, termed the descriptor, to refer to the object type.
Overview
This memo defines a single table: the 802.5 Station Source Routing Table, which contains the source routes known by a end-station on an IEEE 802.5 Token Ring network in which IEEE source-routing is in use.
Source Routing
Source routing extends the 802.5 protocol [8] by assigning a unique ring number to each ring within the extended LAN, and a bridge number to each source routing bridge's connection to a ring. A Routing Information Field (RIF) must be included in frames which need to traverse multiple rings. The format of the RIF is:
octets octets octets octets
1&2 3&4 5&6 17&18
+------+------+------+-------+------+
| RC | RD | RD | ... | RD |
+------+------+------+-------+------+
<---- 0 to 8 RD fields ---->
The format of the Routing Control (RC) field is:
octet 1 octet 2
+---------------+---------------+
|b b b l l l l l|d f f f 0 0 0 0|
+---------------+---------------+
^ ^ ^ ^
| | | |
Explorer indicator --+ | | +-- Max frame length*
Length of RIF field --+ +-- Direction to use RDs
* Note that the length of the Maximum frame length subfield has recently been extended to 6 bits.
The format of each Routing Descriptor (RD) field is:
octet 1 octet 2
+---------------+---------------+
|r r r r r r r r r r r r i i i i|
+---------------+---------------+
<---- ring number ----> <----->
^
|
bridge number --+
Relationship to RFC 1748
RFC 1748 [6], the IEEE 802.5 MIB, defines managed objects used for interfaces to IEEE 802.5 Token Ring subnetworks. This memo is an incremental update to RFC 1748, and is documented independently solely due to the maturity of the definitions contained within RFC 1748.
Relationship to RFC 1525
RFC 1525 [7] defines the MIB objects specific to source-routing for source-routing and SRT bridges. This memo defines the MIB objects specific to source-routing for source-routing end-stations.
Static Source Routes
It is unclear how many, if any, existing systems allow the creation or deletion of "static" 802.5 source routes by network management. However, SNMPv2 SMI defines that the MAX-ACCESS clause as specifying the maximal level of access which makes "protocol sense". Thus, this memo provides support for static source routes through the dot5SrRouteStatus object, but the conformance statements allow for stations which do not support static source routes, by requiring that compliant agents only need provide read-access to dot5SrRouteStatus.
Destinations on the Local Ring
Entries should be included in the dot5SrRouteTable for destination MAC addresses which are on the same ring as the instrumented 802.5 interface. For such entries, dot5SrRouteDescr has the value of the zero-length string, and dot5SrRouteControl has the corresponding value.
Definitions
TOKENRING-STATION-SR-MIB DEFINITIONS ::= BEGIN
IMPORTS
MODULE-IDENTITY, OBJECT-TYPE
FROM SNMPv2-SMI
TEXTUAL-CONVENTION, RowStatus, MacAddress
FROM SNMPv2-TC
MODULE-COMPLIANCE, OBJECT-GROUP FROM SNMPv2-CONF
mib-2, ifIndex FROM RFC1213-MIB;
dot5SrMIB MODULE-IDENTITY
LAST-UPDATED "9412161000Z"
ORGANIZATION "IETF Interfaces MIB Working Group"
CONTACT-INFO
" Keith McCloghrie
Postal: Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-1706
US
Phone: +1 408 526 5260
Email: [email protected]"
DESCRIPTION
"The MIB module for managing source routes in
end-stations on IEEE 802.5 Token Ring networks."
::= { mib-2 42 }
dot5SrMIBObjects OBJECT IDENTIFIER ::= { dot5SrMIB 1 }
SourceRoute ::= TEXTUAL-CONVENTION
DISPLAY-HINT "1x:"
STATUS current
DESCRIPTION
"Represents a Source Route, containing an
embedded sequence of bridge and ring ID's,
as used by 802.5 Source Routing."
REFERENCE "Annex C of ISO/IEC 10038: 1993,
[ANSI/IEEE Std 802.1D, 1993]"
SYNTAX OCTET STRING (SIZE(0..30))
-- The 802.5 Station Source Route Table --
dot5SrRouteTable OBJECT-TYPE
SYNTAX SEQUENCE OF Dot5SrRouteEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table of source-routing routes.
This represents the 802.5 RIF database."
::= { dot5SrMIBObjects 1 }
dot5SrRouteEntry OBJECT-TYPE
SYNTAX Dot5SrRouteEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Information on a specific route.
An entry is created whenever a 'Single Path
Explorer' or an 'All Paths Explorer' discovers
a route to a neighbor not currently in the table,
or whenever an 'All Paths Explorer' discovers a
better (e.g., shorter) route than the route currently
stored in the table. This is done on behalf of
any network layer client.
The ifIndex value in the INDEX clause refers to
the value of MIB-II's ifIndex object for the
interface on which the route is in effect."
INDEX { ifIndex, dot5SrRouteDestination }
::= { dot5SrRouteTable 1 }
Dot5SrRouteEntry ::= SEQUENCE {
dot5SrRouteDestination MacAddress, dot5SrRouteControl OCTET STRING, dot5SrRouteDescr SourceRoute, dot5SrRouteStatus RowStatus
}
dot5SrRouteDestination OBJECT-TYPE
SYNTAX MacAddress
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The destination of this route."
::= { dot5SrRouteEntry 2 }
dot5SrRouteControl OBJECT-TYPE
SYNTAX OCTET STRING (SIZE(2))
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The value of Routing Control field for this
route."
REFERENCE "Annex C of ISO/IEC 10038: 1993,
[ANSI/IEEE Std 802.1D, 1993]"
::= { dot5SrRouteEntry 3 }
dot5SrRouteDescr OBJECT-TYPE
SYNTAX SourceRoute
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The embedded sequence of bridge and ring ID's
for this route. For destinations on the
local ring, the value of this object is
the zero-length string."
REFERENCE "Annex C of ISO/IEC 10038: 1993,
[ANSI/IEEE Std 802.1D, 1993]"
::= { dot5SrRouteEntry 4 }
dot5SrRouteStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this row. Values of the instances
of dot5SrRouteControl and dot5SrRouteDescr can be
modified while the row's status is 'active."
::= { dot5SrRouteEntry 5 }
-- conformance information
dot5SrConformance OBJECT IDENTIFIER ::= { dot5SrMIB 2 }
dot5SrGroups OBJECT IDENTIFIER ::= { dot5SrConformance 1 } dot5SrCompliances OBJECT IDENTIFIER ::= { dot5SrConformance 2 }
-- compliance statements
dot5SrCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for SNMPv2 entities
which implement the IEEE 802.5 Station Source Route
MIB."
MODULE -- this module
MANDATORY-GROUPS { dot5SrRouteGroup }
OBJECT dot5SrRouteStatus
SYNTAX INTEGER { active(1) } -- subset of values
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and only the 'active'
value need be supported."
OBJECT dot5SrRouteControl
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT dot5SrRouteDescr
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
::= { dot5SrCompliances 1 }
-- units of conformance
dot5SrRouteGroup OBJECT-GROUP
OBJECTS { dot5SrRouteControl,
dot5SrRouteDescr,
dot5SrRouteStatus
}
STATUS current
DESCRIPTION
"A collection of objects providing for the management of
source routes in stations on IEEE 802.5 source-routing
networks."
::= { dot5SrGroups 1 }
END
Acknowledgements
The need for this MIB module was agreed upon by the members of the IETF Interfaces Working Group, and the definitions were derived from experience with enterprise-specific MIBs presented to the Working Group.
References
[1] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Structure
of Management Information for version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1442, SNMP Research,Inc., Hughes LAN Systems, Dover Beach Consulting, Inc., Carnegie Mellon University, April 1993.
[2] McCloghrie, K., and M. Rose, Editors, "Management Information
Base for Network Management of TCP/IP-based internets: MIB- II", STD 17, RFC 1213, Hughes LAN Systems, Performance Systems International, March 1991.
[3] Galvin, J., and K. McCloghrie, "Administrative Model for version
2 of the Simple Network Management Protocol (SNMPv2)", RFC 1445, Trusted Information Systems, Hughes LAN Systems, April 1993.
[4] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Protocol
Operations for version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1448, SNMP Research,Inc., Hughes LAN Systems, Dover Beach Consulting, Inc., Carnegie Mellon University, April 1993.
[5] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Textual
Conventions for version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1443, SNMP Research Inc., Hughes LAN Systems, Dover Beach Consulting, Inc., Carnegie Mellon University, April 1993.
[6] McCloghrie, K., and E. Decker, "IEEE 802.5 Token Ring MIB using
SMIv2", RFC 1748 cisco Systems, Inc., December 1994.
[7] McCloghrie, K., Decker, E., Langville, P., and A. Rijsinghani,
"Definitions of Managed Objects for Source Routing Bridges", RFC 1525, Hughes LAN Systems, cisco Systems, Inc., Digital Equipment Corporation, September 1993.
[8] "Token Ring Access Method and Physical Layer Specifications",
IEEE Standard 802.5-1989, 1989.
[9] "Information technology - Local and metropolitan area networks -
Part 5: Token ring access method and physical layer specifications", ISO/IEC 8802-5, 1992.
[10] "Information technology - Telecommunications and information exchange between systems - Local area networks - Media access control (MAC) bridges", ISO/IEC 10038, 1993 [ANSI/IEEE Std 802.1D, 1993 Edition].
[11] "Source Routing Operation by End Systems", ISO/IEC 8802-2 PDAM5.3 (6N7721).
Security Considerations
Security issues are not discussed in this memo.
Authors' Addresses
Keith McCloghrie cisco Systems, Inc. 170 West Tasman Drive, San Jose CA 95134-1706.
Phone: (408) 526-5260 EMail: [email protected]
Fred Baker cisco Systems, Inc. 519 Lado Drive Santa Barbara, CA 93111
Phone: (805) 681-0115 EMail: [email protected]
Eric B. Decker cisco Systems, Inc. 1525 O'Brien Dr. Menlo Park, California 94025
Phone: (415) 688-8241 EMail: [email protected]
