rfc3410.txt

开发snmp的开发包有两个开放的SNMP开发库

Network Working Group                                            J. Case
Request for Comments: 3410                           SNMP Research, Inc.
Obsoletes: 2570                                                 R. Mundy
Category: Informational                  Network Associates Laboratories
                                                              D. Partain
                                                                Ericsson
                                                              B. Stewart
                                                                 Retired
                                                           December 2002


             Introduction and Applicability Statements for
                 Internet Standard Management Framework

Status of this Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet-standard of any kind.  Distribution of this
   memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2002).  All Rights Reserved.

Abstract

   The purpose of this document is to provide an overview of the third
   version of the Internet-Standard Management Framework, termed the
   SNMP version 3 Framework (SNMPv3).  This Framework is derived from
   and builds upon both the original Internet-Standard Management
   Framework (SNMPv1) and the second Internet-Standard Management
   Framework (SNMPv2).

   The architecture is designed to be modular to allow the evolution of
   the Framework over time.

   The document explains why using SNMPv3 instead of SNMPv1 or SNMPv2 is
   strongly recommended.  The document also recommends that RFCs 1157,
   1441, 1901, 1909 and 1910 be retired by moving them to Historic
   status.  This document obsoletes RFC 2570.











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Table of Contents

   1 Introduction .................................................    2
   2 The Internet Standard Management Framework ...................    3
   2.1 Basic Structure and Components .............................    4
   2.2 Architecture of the Internet Standard Management Framework .    4
   3 The SNMPv1 Management Framework ..............................    5
   3.1 The SNMPv1 Data Definition Language ........................    6
   3.2 Management Information .....................................    6
   3.3 Protocol Operations ........................................    7
   3.4 SNMPv1 Security and Administration .........................    7
   4 The SNMPv2 Management Framework ..............................    8
   5 The SNMPv3 Working Group .....................................    8
   6 SNMPv3 Framework Module Specifications .......................   10
   6.1 Data Definition Language ...................................   11
   6.2 MIB Modules ................................................   12
   6.3 Protocol Operations and Transport Mappings .................   13
   6.4 SNMPv3 Security and Administration .........................   13
   7 Document Summaries ...........................................   14
   7.1 Structure of Management Information ........................   14
   7.1.1 Base SMI Specification ...................................   15
   7.1.2 Textual Conventions ......................................   15
   7.1.3 Conformance Statements ...................................   16
   7.2 Protocol Operations ........................................   16
   7.3 Transport Mappings .........................................   16
   7.4 Protocol Instrumentation ...................................   17
   7.5 Architecture / Security and Administration .................   17
   7.6 Message Processing and Dispatch (MPD) ......................   17
   7.7 SNMP Applications ..........................................   18
   7.8 User-based Security Model (USM) ............................   18
   7.9 View-based Access Control (VACM) ...........................   19
   7.10 SNMPv3 Coexistence and Transition .........................   19
   8 Standardization Status .......................................   20
   8.1 SMIv1 Status ...............................................   20
   8.2 SNMPv1 and SNMPv2 Standardization Status ...................   21
   8.3 Working Group Recommendation ...............................   22
   9 Security Considerations ......................................   22
   10 References ..................................................   22
   11 Editor's Addresses ..........................................   26
   12 Full Copyright Statement ....................................   27

1.  Introduction

   This document is an introduction to the third version of the
   Internet-Standard Management Framework, termed the SNMP version 3
   Management Framework (SNMPv3) and has multiple purposes.





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   First, it describes the relationship between the SNMP version 3
   (SNMPv3) specifications and the specifications of the SNMP version 1
   (SNMPv1) Management Framework, the SNMP version 2 (SNMPv2) Management
   Framework, and the Community-based Administrative Framework for
   SNMPv2.

   Second, it provides a roadmap to the multiple documents which contain
   the relevant specifications.

   Third, this document provides a brief easy-to-read summary of the
   contents of each of the relevant specification documents.

   This document is intentionally tutorial in nature and, as such, may
   occasionally be "guilty" of oversimplification.  In the event of a
   conflict or contradiction between this document and the more detailed
   documents for which this document is a roadmap, the specifications in
   the more detailed documents shall prevail.

   Further, the detailed documents attempt to maintain separation
   between the various component modules in order to specify well-
   defined interfaces between them.  This roadmap document, however,
   takes a different approach and attempts to provide an integrated view
   of the various component modules in the interest of readability.

   This document is a work product of the SNMPv3 Working Group of the
   Internet Engineering Task Force (IETF).

   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 BCP 14, RFC 2119 [1].

2.  The Internet Standard Management Framework

   The third version of the Internet Standard Management Framework (the
   SNMPv3 Framework) is derived from and builds upon both the original
   Internet-Standard Management Framework (SNMPv1) and the second
   Internet-Standard Management Framework (SNMPv2).

   All versions (SNMPv1, SNMPv2, and SNMPv3) of the Internet Standard
   Management SNMP Framework share the same basic structure and
   components.  Furthermore, all versions of the specifications of the
   Internet Standard Management Framework follow the same architecture.









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2.1.  Basic Structure and Components

   An enterprise deploying the Internet Standard Management Framework
   contains four basic components:

   *  several (typically many) managed nodes, each with an SNMP entity
      which provides remote access to management instrumentation
      (traditionally called an agent);

   *  at least one SNMP entity with management applications (typically
      called a manager),

   *  a management protocol used to convey management information
      between the SNMP entities, and

   *  management information.

   The management protocol is used to convey management information
   between SNMP entities such as managers and agents.

   This basic structure is common to all versions of the Internet
   Standard Management Framework; i.e., SNMPv1, SNMPv2, and SNMPv3.

2.2.  Architecture of the Internet Standard Management Framework

   The specifications of the Internet Standard Management Framework are
   based on a modular architecture.  This framework is more than just a
   protocol for moving data.  It consists of:

   *  a data definition language,

   *  definitions of management information (the Management Information
      Base, or MIB),

   *  a protocol definition, and

   *  security and administration.

   Over time, as the Framework has evolved from SNMPv1, through SNMPv2,
   to SNMPv3, the definitions of each of these architectural components
   have become richer and more clearly defined, but the fundamental
   architecture has remained consistent.

   One prime motivator for this modularity was to enable the ongoing
   evolution of the Framework, as is documented in RFC 1052 [2].  When
   originally envisioned, this capability was to be used to ease the
   transition from SNMP-based management of internets to management
   based on OSI protocols.  To this end, the framework was architected



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   with a protocol-independent data definition language and Management
   Information Base along with a MIB-independent protocol.  This
   separation was designed to allow the SNMP-based protocol to be
   replaced without requiring the management information to be redefined
   or reinstrumented.  History has shown that the selection of this
   architecture was the right decision for the wrong reason -- it turned
   out that this architecture has eased the transition from SNMPv1 to
   SNMPv2 and from SNMPv2 to SNMPv3 rather than easing the transition
   away from management based on the Simple Network Management Protocol.

   The SNMPv3 Framework builds and extends these architectural
   principles by:

   *  building on these four basic architectural components, in some
      cases incorporating them from the SNMPv2 Framework by reference,
      and

   *  by using these same layering principles in the definition of new
      capabilities in the security and administration portion of the
      architecture.

   Those who are familiar with the architecture of the SNMPv1 Management
   Framework and the SNMPv2 Management Framework will find many familiar
   concepts in the architecture of the SNMPv3 Management Framework.
   However, in some cases, the terminology may be somewhat different.

3.  The SNMPv1 Management Framework

   The original Internet-Standard Network Management Framework (SNMPv1)
   is defined in the following documents:

   *  STD 16, RFC 1155 [3] which defines the Structure of Management
      Information (SMI), the mechanisms used for describing and naming
      objects for the purpose of management.

   *  STD 16, RFC 1212 [4] which defines a more concise description
      mechanism for describing and naming management information
      objects, but which is wholly consistent with the SMI.

   *  STD 15, RFC 1157 [5] which defines the Simple Network Management
      Protocol (SNMP), the protocol used for network access to managed
      objects and event notification.  Note this document also defines
      an initial set of event notifications.








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   Additionally, two documents are generally considered companions to
   these three:

   *  STD 17, RFC 1213 [6] which contains definitions for the base set
      of management information

   *  RFC 1215 [7] defines a concise description mechanism for defining
      event notifications, which are called traps in the SNMPv1
      protocol.  It also specifies the generic traps from RFC 1157 in
      the concise notation.

   These documents describe the four parts of the first version of the
   SNMP Framework.

3.1.  The SNMPv1 Data Definition Language

   The first two and the last document, i.e., RFCs 1155, 1212, and 1215,
   describe the SNMPv1 data definition language and are often