rfc2895.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

Network Working Group                                       A. Bierman
Request for Comments: 2895                                    C. Bucci
Obsoletes: 2074                                    Cisco Systems, Inc.
Category: Standards Track                                     R. Iddon
                                                            3Com, Inc.
                                                           August 2000


      Remote Network Monitoring MIB Protocol Identifier Reference

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.

Copyright Notice

   Copyright (C) The Internet Society (2000).  All Rights Reserved.

Abstract

   This memo defines a notation describing protocol layers in a protocol
   encapsulation, specifically for use in encoding INDEX values for the
   protocolDirTable, found in the RMON-2 MIB (Remote Network Monitoring
   Management Information Base) [RFC2021].  The definitions for the
   standard protocol directory base layer identifiers are also included.

   The first version of the RMON Protocol Identifiers Document [RFC2074]
   has been split into a standards-track Reference portion (this
   document), and an Informational document.  The RMON Protocol
   Identifier Macros document [RFC2896] now contains the non-normative
   portion of that specification.

   This document obsoletes RFC 2074.














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Table of Contents

   1 The SNMP Network Management Framework ..........................  3
   2 Overview .......................................................  3
   2.1 Terms ........................................................  4
   2.2 Relationship to the Remote Network Monitoring MIB ............  6
   2.3 Relationship to the RMON Protocol Identifier Macros Document .  6
   2.4 Relationship to the ATM-RMON MIB .............................  7
   2.4.1 Port Aggregation ...........................................  7
   2.4.2 Encapsulation Mappings .....................................  7
   2.4.3 Counting ATM Traffic in RMON-2 Collections .................  8
   2.5 Relationship to Other MIBs ...................................  9
   3 Protocol Identifier Encoding ...................................  9
   3.1 ProtocolDirTable INDEX Format Examples ....................... 11
   3.2 Protocol Identifier Macro Format ............................. 12
   3.2.1 Lexical Conventions ........................................ 12
   3.2.2 Notation for Syntax Descriptions ........................... 13
   3.2.3 Grammar for the PI Language ................................ 13
   3.2.4 Mapping of the Protocol Name ............................... 15
   3.2.5 Mapping of the VARIANT-OF Clause ........................... 16
   3.2.6 Mapping of the PARAMETERS Clause ........................... 17
   3.2.6.1 Mapping of the 'countsFragments(0)' BIT .................. 18
   3.2.6.2 Mapping of the 'tracksSessions(1)' BIT ................... 18
   3.2.7 Mapping of the ATTRIBUTES Clause ........................... 18
   3.2.8 Mapping of the DESCRIPTION Clause .......................... 19
   3.2.9 Mapping of the CHILDREN Clause ............................. 19
   3.2.10 Mapping of the ADDRESS-FORMAT Clause ...................... 20
   3.2.11 Mapping of the DECODING Clause ............................ 20
   3.2.12 Mapping of the REFERENCE Clause ........................... 20
   3.3 Evaluating an Index of the ProtocolDirTable .................. 21
   4 Base Layer Protocol Identifier Macros .......................... 22
   4.1 Base Identifier Encoding ..................................... 22
   4.1.1 Protocol Identifier Functions .............................. 22
   4.1.1.1 Function 0: None ......................................... 23
   4.1.1.2 Function 1: Protocol Wildcard Function ................... 23
   4.2 Base Layer Protocol Identifiers .............................. 24
   4.3 Encapsulation Layers ......................................... 31
   4.3.1 IEEE 802.1Q ................................................ 31
   5 Intellectual Property .......................................... 34
   6 Acknowledgements ............................................... 35
   7 References ..................................................... 35
   8 IANA Considerations ............................................ 39
   9 Security Considerations ........................................ 39
   10 Authors' Addresses ............................................ 40
   Appendix A ....................................................... 41
   11 Full Copyright Statement ...................................... 42





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1.  The SNMP Network Management Framework

   The SNMP Management Framework presently consists of five major
   components:

   o  An overall architecture, described in RFC 2571 [RFC2571].

   o  Mechanisms for describing and naming objects and events for the
      purpose of management. The first version of this Structure of
      Management Information (SMI) is called SMIv1 and described in STD
      16, RFC 1155 [RFC1155], STD 16, RFC 1212 [RFC1212] and RFC 1215
      [RFC1215].  The second version, called SMIv2, is described in STD
      58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC
      2580 [RFC2580].

   o  Message protocols for transferring management information. The
      first version of the SNMP message protocol is called SNMPv1 and
      described in STD 15, RFC 1157 [RFC1157]. A second version of the
      SNMP message protocol, which is not an Internet standards track
      protocol, is called SNMPv2c and described in RFC 1901 [RFC1901]
      and RFC 1906 [RFC1906].  The third version of the message protocol
      is called SNMPv3 and described in RFC 1906 [RFC1906], RFC 2572
      [RFC2572] and RFC 2574 [RFC2574].

   o  Protocol operations for accessing management information. The
      first set of protocol operations and associated PDU formats is
      described in STD 15, RFC 1157 [RFC1157]. A second set of protocol
      operations and associated PDU formats is described in RFC 1905
      [RFC1905].

   o  A set of fundamental applications described in RFC 2573 [RFC2573]
      and the view-based access control mechanism described in RFC 2575
      [RFC2575].

   A more detailed introduction to the current SNMP Management Framework
   can be found in RFC 2570 [RFC2570].

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  Objects in the MIB are
   defined using the mechanisms defined in the SMI.

   This memo does not specify a MIB module.

2.  Overview

   The RMON-2 MIB [RFC2021] uses hierarchically formatted OCTET STRINGs
   to globally identify individual protocol encapsulations in the
   protocolDirTable.



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   This guide contains algorithms and the authoritative set of base
   layer protocol identifier macros, for use within INDEX values in the
   protocolDirTable.

   This is the second revision of this document, and is intended to
   replace the first half of the first RMON-2 Protocol Identifiers
   document. [RFC2074].

2.1.  Terms

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

   Several terms are used throughout this document, as well as in the
   RMON-2 MIB [RFC2021], that should be introduced:

   parent protocol:
        Also called 'parent'; The encapsulating protocol identifier for
        a specific protocol layer, e.g., IP is the parent protocol of
        UDP.  Note that base layers cannot have parent protocols.  This
        term may be used to refer to a specific encapsulating protocol,
        or it may be used generically to refer to any encapsulating
        protocol.

   child protocol:
        Also called 'child'; An encapsulated protocol identifier for a
        specific protocol layer. e.g., UDP is a child protocol of IP.
        This term may be used to refer to a specific encapsulated
        protocol, or it may be used generically to refer to any
        encapsulated protocol.

   layer-identifier:
        An octet string fragment representing a particular protocol
        encapsulation layer or sub-layer.  A fragment consists of
        exactly four octets, encoded in network byte order.  If present,
        child layer-identifiers for a protocol MUST have unique values
        among each other. (See section 3.3 for more details.)

   protocol:
        A particular protocol layer, as specified by encoding rules in
        this document. Usually refers to a single layer in a given
        encapsulation. Note that this term is sometimes used in the
        RMON-2 MIB [RFC2021] to name a fully-specified protocol-
        identifier string.  In such a case, the protocol-identifier
        string is named for its upper-most layer. A named protocol may
        also refer to any encapsulation of that protocol.




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   protocol-identifier string:
        An octet string representing a particular protocol
        encapsulation, as specified by the encoding rules in this
        document. This string is identified in the RMON-2 MIB [RFC2021]
        as the protocolDirID object.  A protocol-identifier string is
        composed of one or more layer-identifiers read from left to
        right.  The left-most layer-identifier specifies a base layer
        encapsulation. Each layer-identifier to the right specifies a
        child layer protocol encapsulation.

   protocol-identifier macro:  Also called a PI macro; A macro-like
        textual construct used to describe a particular networking
        protocol. Only protocol attributes which are important for RMON
        use are documented. Note that the term 'macro' is historical,
        and PI macros are not real macros, nor are they ASN.1 macros.
        The current set of published RMON PI macros can be found in the
        RMON Protocol Identifier Macros document [RFC2896].

        The PI macro serves several purposes:

        - Names the protocol for use within the RMON-2 MIB [RFC2021].
        - Describes how the protocol is encoded into an octet string.
        - Describes how child protocols are identified (if applicable),
          and encoded into an octet string.
        - Describes which protocolDirParameters are allowed for the
          protocol.
        - Describes how the associated protocolDirType object is encoded
          for the protocol.
        - Provides reference(s) to authoritative documentation for the
          protocol.

   protocol-variant-identifier macro:
        Also called a PI-variant macro; A special kind of PI macro, used
        to describe a particular protocol layer, which cannot be
        identified with a deterministic, and (usually) hierarchical
        structure, like most networking protocols.

        Note that the PI-variant macro and the PI-macro are defined with
        a single set of syntax rules (see section 3.2), except that
        different sub-clauses are required for each type.

        A protocol identified with a PI-variant macro is actually a
        variant of a well known encapsulation that may be present in the
        protocolDirTable. This is used to document the IANA assigned
        protocols, which are needed to identify protocols which cannot
        be practically identified by examination of 'appropriate network
        traffic' (e.g. the packets which carry them).  All other
        protocols (which can be identified by examination of appropriate



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        network traffic) SHOULD be documented using the protocol-
        identifier macro.  (See section 3.2 for details.)

   protocol-parameter:
        A single octet, corresponding to a specific layer-identifier in
        the protocol-identifier. This octet is a bit-mask indicating
        special functions or capabilities that this agent is providing
        for the corresponding protocol.  (See section 3.2.6 for
        details.)

   protocol-parameters string:
        An octet string, which contains one protocol-parameter for each
        layer-identifier in the protocol-identifier.  This string is
        identified in the RMON-2 MIB [RFC2021] as the
        protocolDirParameters object. (See the section 3.2.6 for
        details.)

   protocolDirTable INDEX:
        A protocol-identifier and protocol-parameters octet string pair
        that have been converted to an INDEX value, according to the
        encoding rules in section 7.7 of RFC 1902 [RFC1902].

   pseudo-protocol:
        A convention or algorithm used only within this document for the
        purpose of encoding protocol-identifier strings.

   protocol encapsulation tree:
        Protocol encapsulations can be organized into an inverted tree.
        The nodes of the root are the base encapsulations. The children
        nodes, if any, of a node in the tree are the encapsulations of
        child protocols.

2.2.  Relationship to the Remote Network Monitoring MIB

   This document is intended to identify the encoding rules for the
   OCTET STRING objects protocolDirID and protocolDirParameters.  RMON-2
   tables, such as those in the new Protocol Distribution, Host, and
   Matrix groups, use a local INTEGER INDEX (protocolDirLocalIndex)
   rather than complete protocolDirTable INDEX strings, to identify
   protocols for counting purposes.  Only the protocolDirTable uses the
   protocolDirID and protocolDirParameters strings described in this
   document.

   This document is intentionally separated from the RMON-2 MIB objects
   [RFC2021] to allow updates to this document without any republication
   of MIB objects.





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   This document does not discuss auto-discovery and auto-population of
   the protocolDirTable. This functionality is not explicitly defined by
   the RMON standard. An agent SHOULD populate the directory with the