rfc2454.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                                      M. Daniele
Request for Comments: 2454                Compaq Computer Corporation
Category: Standards Track                               December 1998


               IP Version 6 Management Information Base
                    for the User Datagram Protocol

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 (1998).  All Rights Reserved.

Abstract

   This document is one in the series of documents that define various
   MIB objects for IPv6.  Specifically, this document is the MIB module
   which defines managed objects for implementations of the User
   Datagram Protocol (UDP) over IP Version 6 (IPv6).

   This document also recommends a specific policy with respect to the
   applicability of RFC 2013 for implementations of IPv6.  Namely, that
   most of managed objects defined in RFC 2013 are independent of which
   IP versions underlie UDP, and only the UDP listener information is IP
   version-specific.

   This memo defines an experimental portion of the Management
   Information Base (MIB) for use with network management protocols in
   IPv6-based internets.

1.  Introduction

   A management system contains: several (potentially many) nodes, each
   with a processing entity, termed an agent, which has access to
   management instrumentation; at least one management station; and, a
   management protocol, used to convey management information between
   the agents and management stations.  Operations of the protocol are
   carried out under an administrative framework which defines
   authentication, authorization, access control, and privacy policies.





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RFC 2454                    UDP MIB for IPv6               December 1998


   Management stations execute management applications which monitor and
   control managed elements.  Managed elements are devices such as
   hosts, routers, terminal servers, etc., which are monitored and
   controlled via access to their management information.

   Management information is viewed as a collection of managed objects,
   residing in a virtual information store, termed the Management
   Information Base (MIB).  Collections of related objects are defined
   in MIB modules.  These modules are written using a subset of OSI's
   Abstract Syntax Notation One (ASN.1) [1], termed the Structure of
   Management Information (SMI) [2].

2.  Overview

   This document is one in the series of documents that define various
   MIB objects, and statements of conformance, for IPv6.  This document
   defines the required instrumentation for implementations of UDP over
   IPv6.

3.  Transparency of IP versions to UDP

   The fact that UDP is carried over IPv6 as opposed to IPv4, is largely
   invisible to a UDP implementation.  A "UDPng" did not need to be
   defined, implementations simply need to support IPv6 addresses.

   As such, the managed objects already defined in [UDP MIB] are
   sufficient for managing UDP in the presence of IPv6.  These objects
   are equally applicable whether the managed node supports IPv4 only,
   IPv6 only, or both IPv4 and IPv6.

   For example, udpInDatagrams counts "The total number of UDP datagrams
   delivered to UDP users", regardless of which version of IP is used to
   deliver any of those datagrams.

   Stated differently, UDP implementations don't need separate counters
   for IPv4 and for IPv6.

4.  Representing UDP Listeners

   The exception to the statements in section 3 is the udpTable.  Since
   IPv6 addresses cannot be represented with the IpAddress syntax, not
   all UDP endpoints can be represented in the udpTable defined in [UDP
   MIB].

   This memo defines a new, separate table to represent only those UDP
   endpoints that utilize an IPv6 address.  UDP endpoints on IPv4
   addresses continue to be represented in udpTable [UDP MIB].




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RFC 2454                    UDP MIB for IPv6               December 1998


   A different approach would have been to define a new table to
   represent all UDP endpoints regardless of IP version.  This would
   require changes to [UDP MIB] and hence to existing (IPv4-only) UDP
   implementations.  The approach suggested in this memo has the
   advantage of leaving IPv4-only implementations intact.

   It is assumed that the objects defined in this memo will eventually
   be defined in an update to [UDP MIB].  For this reason, the module
   identity is assigned under the experimental portion of the MIB.

5.  Conformance

   This memo contains conformance statements to define conformance to
   this MIB for UDP over IPv6 implementations.

6.  Definitions

IPV6-UDP-MIB DEFINITIONS ::= BEGIN

IMPORTS
   MODULE-COMPLIANCE, OBJECT-GROUP      FROM SNMPv2-CONF
   MODULE-IDENTITY, OBJECT-TYPE,
   mib-2, experimental                  FROM SNMPv2-SMI
   Ipv6Address, Ipv6IfIndexOrZero       FROM IPV6-TC;

ipv6UdpMIB MODULE-IDENTITY
   LAST-UPDATED "9801290000Z"
   ORGANIZATION "IETF IPv6 MIB Working Group"
   CONTACT-INFO
        "               Mike Daniele

                Postal: Compaq Computer Corporation
                        110 Spitbrook Rd
                        Nashua, NH 03062.
                        US

                Phone:  [phone]
                Email:  [e-mail]"
   DESCRIPTION
        "The MIB module for entities implementing UDP over IPv6."
   ::= { experimental 87 }

-- objects specific to UDP for IPv6

udp      OBJECT IDENTIFIER ::= { mib-2 7 }

-- the UDP over IPv6 Listener table




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RFC 2454                    UDP MIB for IPv6               December 1998


-- This table contains information about this entity's
-- UDP/IPv6 endpoints.  Only endpoints utilizing IPv6 addresses
-- are contained in this table.  This entity's UDP/IPv4 endpoints
-- are contained in udpTable.

ipv6UdpTable OBJECT-TYPE
   SYNTAX      SEQUENCE OF Ipv6UdpEntry
   MAX-ACCESS  not-accessible
   STATUS      current
   DESCRIPTION
        "A table containing UDP listener information for
         UDP/IPv6 endpoints."
   ::= { udp 6 }

ipv6UdpEntry OBJECT-TYPE
   SYNTAX      Ipv6UdpEntry
   MAX-ACCESS  not-accessible
   STATUS      current
   DESCRIPTION
        "Information about a particular current UDP listener.

         Note that conceptual rows in this table require an
         additional index object compared to udpTable, since
         IPv6 addresses are not guaranteed to be unique on the
         managed node."
   INDEX   { ipv6UdpLocalAddress,
             ipv6UdpLocalPort,
             ipv6UdpIfIndex }
   ::= { ipv6UdpTable 1 }

Ipv6UdpEntry ::= SEQUENCE {
   ipv6UdpLocalAddress    Ipv6Address,
   ipv6UdpLocalPort       INTEGER (0..65535),
   ipv6UdpIfIndex         Ipv6IfIndexOrZero }

ipv6UdpLocalAddress OBJECT-TYPE
   SYNTAX       Ipv6Address
   MAX-ACCESS   not-accessible
   STATUS       current
   DESCRIPTION
        "The local IPv6 address for this UDP listener.
         In the case of a UDP listener which is willing
         to accept datagrams for any IPv6 address
         associated with the managed node, the value ::0
         is used."
   ::= { ipv6UdpEntry 1 }

ipv6UdpLocalPort OBJECT-TYPE



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RFC 2454                    UDP MIB for IPv6               December 1998


    SYNTAX     INTEGER (0..65535)
    MAX-ACCESS not-accessible
    STATUS     current
    DESCRIPTION
        "The local port number for this UDP listener."
    ::= { ipv6UdpEntry 2 }

ipv6UdpIfIndex OBJECT-TYPE
   SYNTAX     Ipv6IfIndexOrZero
   MAX-ACCESS   read-only
   STATUS     current
   DESCRIPTION
        "An index object used to disambiguate conceptual rows in
         the table, since the ipv6UdpLocalAddress/ipv6UdpLocalPort
         pair may not be unique.

         This object identifies the local interface that is
         associated with ipv6UdpLocalAddress for this UDP listener.
         If such a local interface cannot be determined, this object
         should take on the value 0.  (A possible example of this
         would be if the value of ipv6UdpLocalAddress is ::0.)

         The interface identified by a particular non-0 value of
         this index is the same interface as identified by the same