rfc4001.txt

用于snmp协议的mib管理软件

Network Working Group                                         M. Daniele
Request for Comments: 4001                           SyAM Software, Inc.
Obsoletes: 3291                                              B. Haberman
Category: Standards Track                       Johns Hopkins University
                                                             S. Routhier
                                                Wind River Systems, Inc.
                                                        J. Schoenwaelder
                                         International University Bremen
                                                           February 2005


           Textual Conventions for Internet Network Addresses

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 (2005).

Abstract

   This MIB module defines textual conventions to represent commonly
   used Internet network layer addressing information.  The intent is
   that these textual conventions will be imported and used in MIB
   modules that would otherwise define their own representations.




















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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  2
   2.  The Internet-Standard Management Framework . . . . . . . . . .  4
   3.  Definitions  . . . . . . . . . . . . . . . . . . . . . . . . .  5
   4.  Usage Hints  . . . . . . . . . . . . . . . . . . . . . . . . . 13
       4.1.  Table Indexing . . . . . . . . . . . . . . . . . . . . . 14
       4.2.  Uniqueness of Addresses  . . . . . . . . . . . . . . . . 14
       4.3.  Multiple Addresses per Host  . . . . . . . . . . . . . . 15
       4.4.  Resolving DNS Names  . . . . . . . . . . . . . . . . . . 15
   5.  Table Indexing Example . . . . . . . . . . . . . . . . . . . . 15
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 17
   7.  Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 18
   8.  Changes from RFC 3291 to RFC 4001  . . . . . . . . . . . . . . 18
   9.  Changes from RFC 2851 to RFC 3291  . . . . . . . . . . . . . . 18
   10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 19
       10.1. Normative References . . . . . . . . . . . . . . . . . . 19
       10.2. Informative References . . . . . . . . . . . . . . . . . 20
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 21
   Full Copyright Statement . . . . . . . . . . . . . . . . . . . . . 22

1.  Introduction

   Several standards-track MIB modules use the IpAddress SMIv2 base
   type.  This limits the applicability of these MIB modules to IP
   Version 4 (IPv4), as the IpAddress SMIv2 base type can only contain
   4-byte IPv4 addresses.  The IpAddress SMIv2 base type has become
   problematic with the introduction of IP Version 6 (IPv6) addresses
   [RFC3513].

   This document defines multiple textual conventions (TCs) as a means
   to express generic Internet network layer addresses within MIB module
   specifications.  The solution is compatible with SMIv2 (STD 58) and
   SMIv1 (STD 16).  New MIB definitions that have to express network
   layer Internet addresses SHOULD use the textual conventions defined
   in this memo.  New MIB modules SHOULD NOT use the SMIv2 IpAddress
   base type anymore.

   A generic Internet address consists of two objects: one whose syntax
   is InetAddressType, and another whose syntax is InetAddress.  The
   value of the first object determines how the value of the second is
   encoded.  The InetAddress textual convention represents an opaque
   Internet address value.  The InetAddressType enumeration is used to
   "cast" the InetAddress value into a concrete textual convention for
   the address type.  This usage of multiple textual conventions allows
   expression of the display characteristics of each address type and
   makes the set of defined Internet address types extensible.




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   The textual conventions for well-known transport domains support
   scoped Internet addresses.  The scope of an Internet address is a
   topological span within which the address may be used as a unique
   identifier for an interface or set of interfaces.  A scope zone (or,
   simply, a zone) is a concrete connected region of topology of a given
   scope.  Note that a zone is a particular instance of a topological
   region, whereas a scope is the size of a topological region
   [RFC4007].  Since Internet addresses on devices that connect multiple
   zones are not necessarily unique, an additional zone index is needed
   on these devices to select an interface.  The textual conventions
   InetAddressIPv4z and InetAddressIPv6z are provided to support
   Internet addresses that include a zone index.  To support arbitrary
   combinations of scoped Internet addresses, MIB authors SHOULD use a
   separate InetAddressType object for each InetAddress object.

   The textual conventions defined in this document can also be used to
   represent generic Internet subnets and Internet address ranges.  A
   generic Internet subnet is represented by three objects: one whose
   syntax is InetAddressType, a second one whose syntax is InetAddress,
   and a third one whose syntax is InetAddressPrefixLength.  The
   InetAddressType value again determines the concrete format of the
   InetAddress value, whereas the InetAddressPrefixLength identifies the
   Internet network address prefix.

   A generic range of consecutive Internet addresses is represented by
   three objects.  The first one has the syntax InetAddressType, and the
   remaining objects have the syntax InetAddress and specify the start
   and end of the address range.  Again, the InetAddressType value
   determines the format of the InetAddress values.

   The textual conventions defined in this document can be used to
   define Internet addresses by using DNS domain names in addition to
   IPv4 and IPv6 addresses.  A MIB designer can write compliance
   statements to express that only a subset of the possible address
   types must be supported by a compliant implementation.

   MIB developers who need to represent Internet addresses SHOULD use
   these definitions whenever applicable, as opposed to defining their
   own constructs.  Even MIB modules that only need to represent IPv4 or
   IPv6 addresses SHOULD use the InetAddressType/InetAddress textual
   conventions defined in this memo.

   There are many widely deployed MIB modules that use IPv4 addresses
   and that have to be revised to support IPv6.  These MIB modules can
   be categorized as follows:






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   1.  MIB modules that define management information that is, in
       principle, IP version neutral, but the MIB currently uses
       addressing constructs specific to a certain IP version.

   2.  MIB modules that define management information that is specific
       to a particular IP version (either IPv4 or IPv6) and that is very
       unlikely to ever be applicable to another IP version.

   MIB modules of the first type SHOULD provide object definitions
   (e.g., tables) that work with all versions of IP.  In particular,
   when revising a MIB module that contains IPv4 specific tables, it is
   suggested to define new tables using the textual conventions defined
   in this memo that support all versions of IP.  The status of the new
   tables SHOULD be "current", whereas the status of the old IP version
   specific tables SHOULD be changed to "deprecated".  The other
   approach, of having multiple similar tables for different IP
   versions, is strongly discouraged.

   MIB modules of the second type, which are inherently IP version
   specific, do not need to be redefined.  Note that even in this case,
   any additions to these MIB modules or to new IP version specific MIB
   modules SHOULD use the textual conventions defined in this memo.

   MIB developers SHOULD NOT use the textual conventions defined in this
   document to represent generic transport layer addresses.  A special
   set of textual conventions for this purpose is defined in RFC 3419
   [RFC3419].

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

2.  The Internet-Standard Management Framework

   For a detailed overview of the documents that describe the current
   Internet-Standard Management Framework, please refer to section 7 of
   RFC 3410 [RFC3410].

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  MIB objects are generally
   accessed through the Simple Network Management Protocol (SNMP).
   Objects in the MIB are defined using the mechanisms defined in the
   Structure of Management Information (SMI).  This memo specifies a MIB
   module that is compliant to the SMIv2, which is described in STD 58,
   RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580
   [RFC2580].





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3.  Definitions

INET-ADDRESS-MIB DEFINITIONS ::= BEGIN

IMPORTS
    MODULE-IDENTITY, mib-2, Unsigned32 FROM SNMPv2-SMI
    TEXTUAL-CONVENTION                 FROM SNMPv2-TC;

inetAddressMIB MODULE-IDENTITY
    LAST-UPDATED "200502040000Z"
    ORGANIZATION
        "IETF Operations and Management Area"
    CONTACT-INFO
        "Juergen Schoenwaelder (Editor)
         International University Bremen
         P.O. Box 750 561
         28725 Bremen, Germany

         Phone: [phone]
         EMail: [e-mail]

         Send comments to <[e-mail]>."
    DESCRIPTION
        "This MIB module defines textual conventions for
         representing Internet addresses.  An Internet
         address can be an IPv4 address, an IPv6 address,
         or a DNS domain name.  This module also defines
         textual conventions for Internet port numbers,
         autonomous system numbers, and the length of an
         Internet address prefix.

         Copyright (C) The Internet Society (2005).  This version
         of this MIB module is part of RFC 4001, see the RFC
         itself for full legal notices."
    REVISION     "200502040000Z"
    DESCRIPTION
        "Third version, published as RFC 4001.  This revision
         introduces the InetZoneIndex, InetScopeType, and
         InetVersion textual conventions."
    REVISION     "200205090000Z"
    DESCRIPTION
        "Second version, published as RFC 3291.  This
         revision contains several clarifications and
         introduces several new textual conventions:
         InetAddressPrefixLength, InetPortNumber,
         InetAutonomousSystemNumber, InetAddressIPv4z,
         and InetAddressIPv6z."
    REVISION     "200006080000Z"



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    DESCRIPTION
        "Initial version, published as RFC 2851."
    ::= { mib-2 76 }

InetAddressType ::= TEXTUAL-CONVENTION
    STATUS      current
    DESCRIPTION
        "A value that represents a type of Internet address.

         unknown(0)  An unknown address type.  This value MUST
                     be used if the value of the corresponding
                     InetAddress object is a zero-length string.
                     It may also be used to indicate an IP address
                     that is not in one of the formats defined
                     below.

         ipv4(1)     An IPv4 address as defined by the
                     InetAddressIPv4 textual convention.

         ipv6(2)     An IPv6 address as defined by the
                     InetAddressIPv6 textual convention.

         ipv4z(3)    A non-global IPv4 address including a zone