rfc1513.txt

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Network Working Group                                      S. Waldbusser
Request for Comments: 1513                    Carnegie Mellon University
Updates: 1271                                             September 1993


       Token Ring Extensions to the Remote Network Monitoring MIB

Status of this Memo

   This RFC 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" for the standardization state and status
   of this protocol.  Distribution of this memo is unlimited.

Abstract

   This memo defines extensions to the Remote Network Monitoring MIB for
   managing 802.5 Token Ring networks.

   The Remote Network Monitoring MIB, RFC 1271, defines a framework for
   remote monitoring functions implemented on a network probe.  That MIB
   defines objects broken down into nine functional groups.  Some of
   those functional groups, the statistics and the history groups, have
   a view of the data-link layer that is specific to the media type and
   require specific objects to be defined for each media type.  RFC 1271
   defined those specific objects necessary for Ethernet.  This
   companion memo defines those specific objects necessary for Token
   Ring LANs.

   In addition, this memo defines some additional monitoring functions
   specifically for Token Ring.  These are defined in the Ring Station
   Group, the Ring Station Order Group, the Ring Station Configuration
   Group, and the Source Routing Statistics Group.

Table of Contents

   1. The Network Management Framework ......................    2
   2. Guidelines for implementing RFC1271 objects on a
      Token Ring network ....................................    3
   2.1 Host Group ...........................................    3
   2.2 Matrix Group .........................................    3
   2.3 Filter Group .........................................    3
   2.4 Other comments .......................................    4
   3. Overview of the RMON Token Ring Extensions MIB ........    4
   3.1 The Token Ring Statistics Groups .....................    4
   3.2 The Token Ring History Groups ........................    5
   3.3 The Token Ring Ring Station Group ....................    5



Waldbusser                                                      [Page 1]

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   3.4 The Token Ring Ring Station Order Group ..............    5
   3.5 The Token Ring Ring Station Config Group .............    5
   3.6 The Token Ring Source Routing Group ..................    5
   4. Terminology ...........................................    5
   5. Definitions ...........................................    6
   5.1 The Token Ring Mac-Layer Statistics Group ............    6
   5.2 The Token Ring Promiscuous Statistics Group ..........   14
   5.3 The Token Ring Mac-Layer History Group ...............   19
   5.4 The Token Ring Promiscuous History Group .............   27
   5.5 The Token Ring Ring Station Group ....................   32
   5.6 The Token Ring Ring Station Order Group ..............   41
   5.7 The Token Ring Ring Station Config Group .............   43
   5.8 The Token Ring Source Routing Group ..................   47
   6. References ............................................   54
   7. Acknowledgments .......................................   55
   8. Security Considerations ...............................   55
   9. Author's Address ......................................   55

1.  The Network Management Framework

   The Internet-standard Network Management Framework consists of three
   components.  They are:

      STD 16, RFC 1155 [1] which defines the SMI, the mechanisms used
      for describing and naming objects for the purpose of management.
      STD 16, RFC 1212 [2] defines a more concise description mechanism,
      which is wholly consistent with the SMI.

      STD 17, RFC 1213 [3] which defines MIB-II, the core set of managed
      objects for the Internet suite of protocols.

      STD 15, RFC 1157 [4] which defines the SNMP, the protocol used for
      network access to managed objects.

   The Framework permits new objects to be defined for the purpose of
   experimentation and evaluation.

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  Within a given MIB module,
   objects are defined using STD 16, RFC 1212's OBJECT-TYPE macro.  At a
   minimum, each object has a name, a syntax, an access-level, and an
   implementation-status.

   The name is an object identifier, an administratively assigned name,
   which specifies an object type.  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 object descriptor, to also refer to the object type.



Waldbusser                                                      [Page 2]

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   The syntax of an object type defines the abstract data structure
   corresponding to that object type.  The ASN.1[5] language is used for
   this purpose.  However, STD 16, RFC 1155 purposely restricts the
   ASN.1 constructs which may be used.  These restrictions are
   explicitly made for simplicity.

   The access-level of an object type defines whether it makes "protocol
   sense" to read and/or write the value of an instance of the object
   type.  (This access-level is independent of any administrative
   authorization policy.)

   The implementation-status of an object type indicates whether the
   object is mandatory, optional, obsolete, or deprecated.

2.  Guidelines for implementing RFC1271 objects on a Token
    Ring network

   Wherever a MacAddress is to be used in this MIB the source routing
   bit is stripped off.  The resulting address will be consistently
   valid for all packets sent by a particular node.

2.1.  Host Group

   Only Token Ring isolating errors will increment the error counter for
   a particular hostEntry.  The isolating errors are: LineErrors,
   BurstErrors, ACErrors, InternalErrors, and AbortErrors.  ACErrors
   will increment the error counter only for the nearest upstream
   neighbor of the station reporting the error.  LineErrors and
   BurstErrors will increment the error counters for the station
   reporting the error and its neighbor upstream neighbor.
   InternalErrors and AbortErrors will increment the error counter for
   the station reporting the error only.  In addition, congestionErrors
   will also be counted for each hostEntry. These errors will be
   incremented in the host entry of the station that reports the errors
   in an error report frame.

   The hostOutPkts and hostOutOctets counters shall not be incremented
   for packets with errors.

2.2.  Matrix Group

   Error counters are never incremented.

2.3.  Filter Group

   The following conditions make up the status bitmask for token ring
   networks:




Waldbusser                                                      [Page 3]

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               bit #    Error
                   3    First packet after some packets were dropped
                   4    Packet with the Frame Copied Bit set
                   5    Packet with the Address Recognized Bit set

   For the purpose of the packet match algorithm, the filters assume a
   32 byte RIF field.  Thus, when matching, the filter is compared to
   the packet starting at the AC byte of the packet, until the end of
   the RIF field; then the unused RIF bytes in the filter are skipped
   and matching proceeds from that point.  Any filter "care" bits in the
   RIF that don't correspond to bytes in the input packet will cause the
   filter to fail.

2.4.  Other comments

   Because soft error report packets may be sent with assured delivery,
   some errors may be accidently reported twice on devices that perform
   the RMON function promiscuously.

3.  Overview of the RMON Token Ring Extensions MIB

   The Remote Network Monitoring MIB, RFC 1271, defines a framework for
   remote monitoring functions implemented on a network probe.  That MIB
   defines objects broken down into nine functional groups.  Some of
   those functional groups, the statistics and the history groups, have
   a view of the data-link layer that is specific to the media type and
   require specific objects to be defined for each media type.  RFC 1271
   defined those specific objects necessary for Ethernet.  This MIB
   defines contains four groups that define those specific objects
   necessary for Token Ring LANs.

   In addition, this memo defines some additional monitoring functions
   specifically for Token Ring.  These are defined in the Ring Station
   Group, the Ring Station Order Group, the Ring Station Configuration
   Group, and the Source Routing Statistics Group.

3.1.  The Token Ring Statistics Groups

   The Token Ring statistics groups contain current utilization and
   error statistics.  The statistics are broken down into two groups,
   the Token Ring Mac-Layer Statistics Group and the Token Ring
   Promiscuous Statistics Group.  The Token Ring Mac-Layer Statistics
   Group collects information from Mac Layer, including error reports
   for the ring and ring utilization of the Mac Layer.  The Token Ring
   Promiscuous Statistics Group collects utilization statistics from
   data packets collected promiscuously.





Waldbusser                                                      [Page 4]

RFC 1513           Token Ring Extensions to RMON MIB      September 1993


3.2.  The Token Ring History Groups

   The Token Ring History Groups contain historical utilization and
   error statistics.  The statistics are broken down into two groups,
   the Token Ring Mac-Layer History Group and the Token Ring Promiscuous
   History Group.  The Token Ring Mac-Layer History Group collects
   information from Mac Layer, including error reports for the ring and
   ring utilization of the Mac Layer.  The Token Ring Promiscuous
   History Group collects utilization statistics from data packets
   collected promiscuously.

3.3.  The Token Ring Ring Station Group

   The Token Ring Ring Station Group contains statistics and status
   information associated with each Token Ring station on the local
   ring.  In addition, this group provides status information for each
   ring being monitored.

3.4.  The Token Ring Ring Station Order Group

   The Token Ring Ring Station Order Group provides the order of the
   stations on monitored rings.

3.5.  The Token Ring Ring Station Config Group

   The Token Ring Ring Station Config Group manages token ring stations
   through active means.  Any station on a monitored ring may be removed
   or have configuration information downloaded from it.

3.6.  The Token Ring Source Routing Group

   The Token Ring Source Routing Group contains utilization statistics
   derived from source routing information optionally present in token
   ring packets.

4.  Terminology

   The 802.5 specification [7] defines the term "good frame" as a frame
   that is bounded by a valid SD and ED, is an integral number of octets
   in length, is composed of only 0 and 1 bits between the SD and the
   ED, has the FF bits of the GC field equal to 00 or 01, has a valid
   FCS, and has a minimum of 18 octets between the SD and the ED.  This
   document will use the term "good frame" in the same manner.








Waldbusser                                                      [Page 5]

RFC 1513           Token Ring Extensions to RMON MIB      September 1993


5.  Definitions

          TOKEN-RING-RMON-MIB DEFINITIONS ::= BEGIN

          IMPORTS
              Counter, TimeTicks          FROM RFC1155-SMI
              OBJECT-TYPE                 FROM RFC-1212
              OwnerString, EntryStatus,   -- Textual Conventions
              rmon, statistics, history
                                          FROM RFC1271-MIB;


             -- All representations of MAC addresses in this MIB
             -- Module use, as a textual convention (i.e. this
             -- convention does not affect their encoding), the
             -- data type:

             MacAddress ::= OCTET STRING (SIZE (6)) -- a 6 octet
                                                    -- address 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.

              TimeInterval ::= INTEGER
              -- A period of time, measured in units of 0.01 seconds.

          --  This MIB module uses the extended OBJECT-TYPE macro as