rfc1398.txt

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Network Working Group                                      F. Kastenholz
Request for Comments: 1398                            FTP Software, Inc.
Obsoletes: 1284                                             January 1993


                   Definitions of Managed Objects for
                   the Ethernet-like Interface Types

Status of this Memo

   This RFC specifies an IAB standards track protocol for the Internet
   community, and requests discussion and suggestions for improvements.
   Please refer to the current edition of the "IAB Official Protocol
   Standards" for the standardization state and status of this protocol.
   Distribution of this memo is unlimited.

Abstract

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in TCP/IP-based internets.
   In particular, it defines objects for managing ethernet-like objects.

Table of Contents

   1. The Network Management Framework ......................    1
   2. Objects ...............................................    2
   2.1 Format of Definitions ................................    2
   3. Overview ..............................................    3
   4. Definitions ...........................................    4
   4.1 The Ethernet-like Statistics Group ...................    4
   4.2 The Ethernet-like Collision Statistics Group .........   11
   4.3 802.3 Tests ..........................................   12
   4.4 802.3 Hardware Chipsets ..............................   14
   5. Change Log ............................................   14
   6. Acknowledgements ......................................   16
   7. References ............................................   16
   8. Security Considerations ...............................   17
   9. Author's Address ......................................   17

1.  The Network Management Framework

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

      STD 16/RFC 1155 [3] which defines the SMI, the mechanisms used for
      describing and naming objects for the purpose of management.  STD
      16/RFC 1212 [13] defines a more concise description mechanism,
      which is wholly consistent with the SMI.



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RFC 1398                   Ethernet-Like MIB                January 1993


      RFC 1156 [4] which defines MIB-I, the core set of managed objects
      for the Internet suite of protocols.  STD 17/RFC 1213 [6] defines
      MIB-II, an evolution of MIB-I based on implementation experience
      and new operational requirements.

      STD 15/RFC 1157 [5] 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.

2.  Objects

   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) [7]
   defined in the SMI.  In particular, each object has a name, a syntax,
   and an encoding.  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.

   The syntax of an object type defines the abstract data structure
   corresponding to that object type.  The ASN.1 language is used for
   this purpose.  However, the SMI [3] purposely restricts the ASN.1
   constructs which may be used.  These restrictions are explicitly made
   for simplicity.

   The encoding of an object type is simply how that object type is
   represented using the object type's syntax.  Implicitly tied to the
   notion of an object type's syntax and encoding is how the object type
   is represented when being transmitted on the network.

   The SMI specifies the use of the basic encoding rules of ASN.1 [8],
   subject to the additional requirements imposed by the SNMP.

2.1.  Format of Definitions

   Section 4 contains contains the specification of all object types
   contained in this MIB module.  The object types are defined using the
   conventions defined in the SMI, as amended by the extensions
   specified in [13].







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RFC 1398                   Ethernet-Like MIB                January 1993


3.  Overview

   Instances of these object types represent attributes of an interface
   to an ethernet-like communications medium.  At present, ethernet-like
   media are identified by three values of the ifType object in the
   Internet-standard MIB:

          ethernet-csmacd(6)
          iso88023-csmacd(7)
          starLan(11)

   For these interfaces, the value of the ifSpecific variable in the
   MIB-II [6] has the OBJECT IDENTIFIER value:

          dot3    OBJECT IDENTIFER ::= { transmission 7 }

   The definitions presented here are based on the IEEE 802.3 Layer
   Management Specification [9], as originally interpreted by Frank
   Kastenholz of Interlan in [10].  Implementors of these MIB objects
   should note that the IEEE document explicitly describes (in the form
   of Pascal pseudocode) when, where, and how various MAC attributes are
   measured.  The IEEE document also describes the effects of MAC
   actions that may be invoked by manipulating instances of the MIB
   objects defined here.

   To the extent that some of the attributes defined in [9] are
   represented by previously defined objects in the Internet- standard
   MIB or in the Generic Interface Extensions MIB [11], such attributes
   are not redundantly represented by objects defined in this memo.
   Among the attributes represented by objects defined in other memos
   are the number of octets transmitted or received on a particular
   interface, the number of frames transmitted or received on a
   particular interface, the promiscuous status of an interface, the MAC
   address of an interface, and multicast information associated with an
   interface.

   The relationship between an ethernet-like interface and an interface
   in the context of the Internet-standard MIB is one-to-one.  As such,
   the value of an ifIndex object instance can be directly used to
   identify corresponding instances of the objects defined herein.











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RFC 1398                   Ethernet-Like MIB                January 1993


4.  Definitions

          RFC1398-MIB DEFINITIONS ::= BEGIN


               IMPORTS
                    Counter, Gauge
                         FROM RFC1155-SMI
                    transmission
                         FROM RFC1213-MIB
                    OBJECT-TYPE
                         FROM RFC-1212;

          --  This MIB module uses the extended OBJECT-TYPE macro as
          --  defined in RFC-1212.

          --  this is the MIB module for ethernet-like objects

          dot3    OBJECT IDENTIFIER ::= { transmission 7 }

          -- { dot3 1 } is obsolete and has been deleted.

4.1.  The Ethernet-like Statistics Group


          -- the Ethernet-like Statistics group

          -- Implementation of this group is mandatory

          dot3StatsTable   OBJECT-TYPE
               SYNTAX    SEQUENCE OF Dot3StatsEntry
               ACCESS    not-accessible
               STATUS    mandatory
               DESCRIPTION
                         "Statistics for a collection of ethernet-like
                         interfaces attached to a particular system."
               ::= { dot3 2 }


          dot3StatsEntry   OBJECT-TYPE
               SYNTAX    Dot3StatsEntry
               ACCESS    not-accessible
               STATUS    mandatory
               DESCRIPTION
                         "Statistics for a particular interface to an
                         ethernet-like medium."
               INDEX     { dot3StatsIndex }
               ::= { dot3StatsTable 1 }



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RFC 1398                   Ethernet-Like MIB                January 1993


          Dot3StatsEntry ::= SEQUENCE {
               dot3StatsIndex
                    INTEGER,
               dot3StatsAlignmentErrors
                    Counter,
               dot3StatsFCSErrors
                    Counter,
               dot3StatsSingleCollisionFrames
                    Counter,
               dot3StatsMultipleCollisionFrames
                    Counter,
               dot3StatsSQETestErrors
                    Counter,
               dot3StatsDeferredTransmissions
                    Counter,
               dot3StatsLateCollisions
                    Counter,
               dot3StatsExcessiveCollisions
                    Counter,
               dot3StatsInternalMacTransmitErrors
                    Counter,
               dot3StatsCarrierSenseErrors
                    Counter,
               dot3StatsFrameTooLongs
                    Counter,
               dot3StatsInternalMacReceiveErrors
                    Counter
          }

          dot3StatsIndex   OBJECT-TYPE
               SYNTAX    INTEGER
               ACCESS    read-only
               STATUS    mandatory
               DESCRIPTION
                         "An index value that uniquely identifies an
                         interface to an ethernet-like medium.  The
                         interface identified by a particular value of
                         this index is the same interface as identified
                         by the same value of ifIndex."
               ::= { dot3StatsEntry 1 }


          dot3StatsAlignmentErrors   OBJECT-TYPE
               SYNTAX    Counter
               ACCESS    read-only
               STATUS    mandatory
               DESCRIPTION
                         "A count of frames received on a particular



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RFC 1398                   Ethernet-Like MIB                January 1993


                         interface that are not an integral number of
                         octets in length and do not pass the FCS check.

                         The count represented by an instance of this
                         object is incremented when the alignmentError
                         status is returned by the MAC service to the
                         LLC (or other MAC user). Received frames for
                         which multiple error conditions obtain are,
                         according to the conventions of IEEE 802.3
                         Layer Management, counted exclusively according
                         to the error status presented to the LLC."
               REFERENCE
                         "IEEE 802.3 Layer Management"
               ::= { dot3StatsEntry 2 }


          dot3StatsFCSErrors   OBJECT-TYPE
               SYNTAX    Counter
               ACCESS    read-only
               STATUS    mandatory
               DESCRIPTION
                         "A count of frames received on a particular
                         interface that are an integral number of octets
                         in length but do not pass the FCS check.

                         The count represented by an instance of this
                         object is incremented when the frameCheckError
                         status is returned by the MAC service to the
                         LLC (or other MAC user). Received frames for
                         which multiple error conditions obtain are,
                         according to the conventions of IEEE 802.3
                         Layer Management, counted exclusively according
                         to the error status presented to the LLC."