rfc1230.txt

<VC++网络游戏建摸与实现>源代码

Network Working Group                                      K. McCloghrie
Request for Comments: 1230                      Hughes LAN Systems, Inc.
                                                                  R. Fox
                                                         Synoptics, Inc.
                                                                May 1991


                        IEEE 802.4 Token Bus MIB

Status of this Memo

   This memo defines a MIB for the IEEE 802.4 Token Bus for use with the
   SNMP protocol.  This memo is a product of the Transmission Working
   Group of the Internet Engineering Task Force (IETF).  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.

Table of Contents

   1. Abstract ..............................................    1
   2. The Network Management Framework.......................    2
   3. Objects ...............................................    2
   3.1 Format of Definitions ................................    3
   4. Overview ..............................................    3
   4.1 Scope of Definitions .................................    3
   4.2 Textual Conventions ..................................    4
   4.3 Optional Objects .....................................    4
   5. Definitions ...........................................    4
   6. Acknowledgements ......................................   22
   7. References ............................................   22
   8. Security Considerations................................   23
   9. Authors' Addresses.....................................   23

1.  Abstract

   This memo defines an experimental portion of the Management
   Information Base (MIB) for use with network management protocols in
   TCP/IP-based internets.  In particular, this memo defines managed
   objects used for managing subnetworks which use the IEEE 802.4 Token
   Bus technology described in 802.4 Token-Passing Bus Access Method and
   Physical Layer Specifications, IEEE Standard 802.4.







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RFC 1230                     IEEE 802.4 MIB                     May 1991


2.  The Network Management Framework

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

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

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

      RFC 1157 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.

3.  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.




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RFC 1230                     IEEE 802.4 MIB                     May 1991


3.1.  Format of Definitions

   Section 5 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 [9,10].

4.  Overview

   This memo defines three tables:

      - the 802.4 Operational Table containing state and
        operational parameter information which is specific to
        802.4 interfaces;

      - the 802.4 Initialization Table containing the parameter
        information used by an 802.4 interface as the values to
        be assigned to its operational parameters upon
        initialization; and

      - the 802.4 Statistics Table containing 802.4 interface
        statistics.

   A managed system will have one entry in each of these tables for each
   of its 802.4 interfaces.

   This memo also defines OBJECT IDENTIFIERs, some to identify 802.4
   tests, for use with the ifExtnsTestTable defined in [11], and some to
   identify Token Bus interface Chip Sets, for use with the
   ifExtnsChipSet object defined in [11].

4.1.  Scope of Definitions

   All objects defined in this memo are registered in a single subtree
   within the experimental namespace [3], and are for use with every
   interface which conforms to the IEEE 802.4 Token Bus Access Method
   [10]. At present, this applies to interfaces for which the ifType
   variable in the Internet-standard MIB [4,6] has the value:

      iso88024-tokenBus(8)

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

      dot4    OBJECT IDENTIFIER ::= { experimental 7 }

   as defined below.




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4.2.  Textual Conventions

   Two new datatypes, MacAddress and OctetTime, are introduced as
   textual conventions in this document.  These textual conventions have
   NO effect on either the syntax nor the semantics of any managed
   object. Objects defined using these conventions are always encoded by
   means of the rules that define their primitive type.  Hence, no
   changes to the SMI or the SNMP are necessary to accommodate these
   textual conventions which are adopted merely for the convenience of
   readers and writers in pursuit of the elusive goal of a concise and
   unambiguous specification.

4.3.  Optional Objects

   A few objects are defined in this memo with "optional" status for the
   purpose of allowing experimentation to determine whether they are
   useful or not.  If sufficient consensus is reached in the Internet
   community to result in a subsequent revision of this memo being
   placed in the Internet-standard MIB, then these optional objects will
   either be removed or become mandatory.

5.  Definitions


          RFC1230-MIB DEFINITIONS ::= BEGIN

          --                 IEEE 802.4 Token Bus MIB

          IMPORTS
                  experimental
                          FROM RFC1155-SMI
                  OBJECT-TYPE
                          FROM RFC-1212;

          --  This MIB Module uses the extended OBJECT-TYPE macro as
          --  defined in [9].



          dot4    OBJECT IDENTIFIER ::= { experimental 7 }

          -- 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



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                                                    -- defined by IEEE
                                                    -- 802.1a.
          -- 16-bit addresses, if needed, are represented by setting
          -- their upper 4 octets to all 0's, i.e., AAFF would be
          -- represented as 00000000AAFF.


          -- This specification follows the 802.4 convention of
          -- specifying time intervals, which are dependent on the
          -- bandwidth of the media, in units of octet time.  One
          -- octet time is the time taken to transmit eight bits.
          -- Representation of such time intervals in this MIB Module
          -- use, as a textual convention (i.e., this convention does
          -- not affect their encoding), the data type:

          OctetTime  ::= INTEGER        -- the value of a time
                                        -- interval in units of octet
                                        -- time.


          -- The 802.4 Operational Table

          -- This table contains state and parameter information which
          -- is specific to 802.4 interfaces.  It is mandatory that
          -- systems having 802.4 interfaces implement this table in
          -- addition to the generic interfaces table [4,6] and its
          -- generic extensions [11].

          dot4Table  OBJECT-TYPE
                     SYNTAX  SEQUENCE OF Dot4Entry
                     ACCESS  not-accessible
                     STATUS  mandatory
                     DESCRIPTION
                             "This table contains Token Bus interface
                             parameters and state variables, one entry
                             per 802.5 interface."

                     ::= { dot4 1 }

          dot4Entry  OBJECT-TYPE
                     SYNTAX  Dot4Entry
                     ACCESS  not-accessible
                     STATUS  mandatory
                     DESCRIPTION
                             "A list of Token Bus status and operational
                             parameter values for an 802.4 interface."
                     INDEX   { dot4IfIndex }
                     ::= { dot4Table 1 }



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RFC 1230                     IEEE 802.4 MIB                     May 1991


          Dot4Entry  ::= SEQUENCE {
                             dot4IfIndex
                                 INTEGER,
                             dot4Options
                                 INTEGER,
                             dot4State
                                 INTEGER,
                             dot4Commands
                                 INTEGER,
                             dot4MacAddrLen
                                 INTEGER,
                             dot4NextStation
                                 MacAddress,
                             dot4PreviousStation
                                 MacAddress,
                             dot4SlotTime
                                 OctetTime,
                             dot4LastTokenRotTime
                                 OctetTime,
                             dot4HiPriTokenHoldTime
                                 OctetTime,
                             dot4TargetRotTimeClass4
                                 OctetTime,
                             dot4TargetRotTimeClass2
                                 OctetTime,
                             dot4TargetRotTimeClass0
                                 OctetTime,
                             dot4TargetRotTimeRingMaint
                                 OctetTime,
                             dot4RingMaintTimerInitValue
                                 OctetTime,
                             dot4MaxInterSolicitCount
                                 INTEGER (16..255),
                             dot4MaxRetries
                                 INTEGER (0..7),
                             dot4MinPostSilencePreambLen
                                 INTEGER,