rfc2924.txt

radius服务器

Network Working Group                                        N. Brownlee
Request for Comments: 2924                    The University of Auckland
Category: Informational                                        A. Blount
                                                         MetraTech Corp.
                                                          September 2000


                Accounting Attributes and Record Formats

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 (2000).  All Rights Reserved.

Abstract

   This document summarises Internet Engineering Task Force (IETF) and
   International Telecommunication Union (ITU-T) documents related to
   Accounting.  A classification scheme for the Accounting Attributes in
   the summarised documents is presented.  Exchange formats for
   Accounting data records are discussed, as are advantages and
   disadvantages of integrated versus separate record formats and
   transport protocols.  This document discusses service definition
   independence, extensibility, and versioning.  Compound service
   definition capabilities are described.

Table of Contents

   1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . .   2
   2. Terminology and Notation . . . . . . . . . . . . . . . . . . .   3
   3. Architecture Model . . . . . . . . . . . . . . . . . . . . . .   4
   4. IETF Documents . . . . . . . . . . . . . . . . . . . . . . . .   4
   4.1. RADIUS . . . . . . . . . . . . . . . . . . . . . . . . . . .   4
   4.1.1. RADIUS Attributes  . . . . . . . . . . . . . . . . . . . .   5
   4.2. DIAMETER . . . . . . . . . . . . . . . . . . . . . . . . . .   6
   4.2.1. DIAMETER Attributes  . . . . . . . . . . . . . . . . . . .   7
   4.3. ROAMOPS  . . . . . . . . . . . . . . . . . . . . . . . . . .   8
   4.4. RTFM . . . . . . . . . . . . . . . . . . . . . . . . . . . .   8
   4.4.1. RTFM Attributes  . . . . . . . . . . . . . . . . . . . . .   9
   4.5. ISDN MIB . . . . . . . . . . . . . . . . . . . . . . . . . .  10
   4.5.1. ISDN Attributes  . . . . . . . . . . . . . . . . . . . . .  10
   4.6. AToMMIB  . . . . . . . . . . . . . . . . . . . . . . . . . .  11
   4.6.1. AToMMIB Attributes . . . . . . . . . . . . . . . . . . . .  11



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RFC 2924        Accounting Attributes and Record Formats  September 2000


   4.7. QoS: RSVP and DIFFSERV . . . . . . . . . . . . . . . . . . .  12
   4.7.1. QoS: RSVP and DIFFSERV Attributes  . . . . . . . . . . . .  13
   5. ITU-T Documents  . . . . . . . . . . . . . . . . . . . . . . .  13
   5.1. Q.825: Call Detail Recording . . . . . . . . . . . . . . . .  13
   5.2. Q.825 Attributes . . . . . . . . . . . . . . . . . . . . . .  14
   6. Other Documents  . . . . . . . . . . . . . . . . . . . . . . .  18
   6.1. TIPHON: ETSI TS 101 321  . . . . . . . . . . . . . . . . . .  18
   6.2. MSIX . . . . . . . . . . . . . . . . . . . . . . . . . . . .  19
   7. Accounting File and Record Formats . . . . . . . . . . . . . .  19
   7.1. ASN.1 Records  . . . . . . . . . . . . . . . . . . . . . . .  19
   7.1.1. RTFM and AToMMIB . . . . . . . . . . . . . . . . . . . . .  19
   7.1.2. Q.825  . . . . . . . . . . . . . . . . . . . . . . . . . .  20
   7.2. Binary Records . . . . . . . . . . . . . . . . . . . . . . .  20
   7.2.1. RADIUS . . . . . . . . . . . . . . . . . . . . . . . . . .  20
   7.2.2. DIAMETER . . . . . . . . . . . . . . . . . . . . . . . . .  20
   7.3. Text Records . . . . . . . . . . . . . . . . . . . . . . . .  21
   7.3.1. ROAMOPS  . . . . . . . . . . . . . . . . . . . . . . . . .  21
   8. AAA Requirements . . . . . . . . . . . . . . . . . . . . . . .  22
   8.1. A Well-defined Set of Attributes . . . . . . . . . . . . . .  22
   8.2. A Simple Interchange Format  . . . . . . . . . . . . . . . .  23
   9. Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . .  23
   9.1. Record Format vs. Protocol . . . . . . . . . . . . . . . . .  24
   9.2. Tagged, Typed Data . . . . . . . . . . . . . . . . . . . . .  24
   9.2.1. Standard Type Definitions  . . . . . . . . . . . . . . . .  25
   9.3. Transaction Identifiers  . . . . . . . . . . . . . . . . . .  26
   9.4. Service Definitions  . . . . . . . . . . . . . . . . . . . .  26
   9.4.1. Service Independence . . . . . . . . . . . . . . . . . . .  27
   9.4.2. Versioned Service Definitions  . . . . . . . . . . . . . .  29
   9.4.3. Relationships Among Usage Events . . . . . . . . . . . . .  29
   9.4.4. Service Namespace Management . . . . . . . . . . . . . . .  30
   10. Encodings . . . . . . . . . . . . . . . . . . . . . . . . . .  30
   11. Security Considerations . . . . . . . . . . . . . . . . . . .  31
   12. References  . . . . . . . . . . . . . . . . . . . . . . . . .  31
   13. Authors' Addresses  . . . . . . . . . . . . . . . . . . . . .  35
   14. Full Copyright Statement  . . . . . . . . . . . . . . . . . .  36

1.  Introduction

   This document summarises IETF and ITU-T documents related to
   Accounting.  For those documents which describe Accounting Attributes
   (i.e. quantities which can be measured and reported), an Attribute
   Summary is given.  Although several of the documents describe
   Attributes which are similar, no attempt is made to identify those
   which are the same in several documents.  An extensible
   classification scheme for AAA Accounting Attributes is proposed; it
   is a superset of the attributes in all the documents summarised.





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   Many existing accounting record formats and protocols [RAD-ACT]
   [TIPHON] are of limited use due to their single-service descriptive
   facilities and lack of extensibility.  While some record formats and
   protocols support extensible attributes [RAD-ACT], none provide
   identification, type checking, or versioning support for defined
   groupings of attributes (service definitions).  This document makes a
   case for well-defined services.

   Advantages and disadvantages of integrated versus separate record
   formats and transport protocols are discussed.  This document
   discusses service definition independence, extensibility, and
   versioning.  Compound service definition capabilities are described.

2.  Terminology and Notation

   The following terms are used throughout the document.

   Accounting Server
      A network element that accepts Usage Events from Service Elements.
      It acts as an interface to back-end rating, billing, and
      operations support systems.

   Attribute-Value Pair (AVP)
      A representation for a Usage Attribute consisting of the name of
      the Attribute and a value.

   Property
      A component of a Usage Event.  A Usage Event describing a phone
      call, for instance, might have a "duration" Property.

   Service
      A type of task that is performed by a Service Element for a
      Service Consumer.

   Service Consumer
      Client of a Service Element.  End-user of a network service.

   Service Definition
      A specification for a particular service.  It is composed of a
      name or other identifier, versioning information, and a collection
      of Properties.

   Service Element
      A network element that provides a service to Service Consumers.
      Examples include RAS devices, voice and fax gateways, conference
      bridges.





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   Usage Attribute
      A component of a Usage Event that describes some metric of service
      usage.

   Usage Event
      The description of an instance of service usage.

3.  Architecture Model

   Service Elements provide Services to Service Consumers.  Before,
   while, and/or after services are provided, the Service Element
   reports Usage Events to an Accounting Server.  Alternately, the
   Accounting Server may query the Service Element for Usage Events.
   Usage events are sent singly or in bulk.

      +------------+       +-----------+              +------------+
      |  Service   |<----->|  Service  | Usage Events | Accounting |
      |  Consumer  |   +-->|  Element  |------------->|   Server   |
      +------------+   |   +-----------+              +------------+
                       |
      +------------+   |
      |  Service   |<--+
      |  Consumer  |
      +------------+

   Accounting Servers may forward Usage Events to other systems,
   possibly in other administrative domains.  These transfers are not
   addressed by this document.

4.  IETF Documents

   In March 1999 there were at least 19 Internet Drafts and 8 RFCs
   concerned with Accounting.  These are summarised (by working group)
   in the following sections.

4.1.  RADIUS

   The RADIUS protocol [RAD-PROT] carries authentication, authorization
   and configuration information between a Network Access Server (NAS)
   and an authentication server.  Requests and responses carried by the
   protocol are expressed in terms of RADIUS attributes such as User-
   Name, Service-Type, and so on.  These attributes provide the
   information needed by a RADIUS server to authenticate users and to
   establish authorized network service for them.

   The protocol was extended to carry accounting information between a
   NAS and a shared accounting server.  This was achieved by defining a
   set of RADIUS accounting attributes [RAD-ACT].



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   RADIUS packets have a short header containing the RADIUS packet type
   and authenticator (sixteen octets) and length, followed by a sequence
   of (Type, Length, Value) triples, one for each attribute.

   RADIUS is very widely used, and a number of significant new
   extensions to it have been proposed.  For example [RAD-EXT] discusses
   extensions to implement the Extensible Authentication Protocol (EAP)
   and the Apple Remote Access Protocol (ARAP).  [RAD-TACC] discusses
   extensions to permit RADIUS to interwork effectively with tunnels
   using protocols such as PPTP and L2TP.

4.1.1.  RADIUS Attributes

   Each RADIUS attribute is identified by an 8-bit number, referred to
   as the RADIUS Type field.  Up-to-date values of this field are
   specified in the most recent Assigned Numbers RFC [ASG-NBR], but the
   current list is as follows:

   RADIUS Attributes [RAD-PROT]             36  Login-LAT-Group
                                            37  Framed-AppleTalk-Link
       1  User-Name                         38  Framed-AppleTalk-Network
       2  User-Password                     39  Framed-AppleTalk-Zone
       3  CHAP-Password
       4  NAS-IP-Address                    60  CHAP-Challenge
       5  NAS-Port                          61  NAS-Port-Type
       6  Service-Type                      62  Port-Limit
       7  Framed-Protocol                   63  Login-LAT-Port
       8  Framed-IP-Address
       9  Framed-IP-Netmask              RADIUS Accounting Attributes
      10  Framed-Routing                 [RAD-ACT]
      11  Filter-Id
      12  Framed-MTU                        40  Acct-Status-Type
      13  Framed-Compression                41  Acct-Delay-Time
      14  Login-IP-Host                     42  Acct-Input-Octets
      15  Login-Service                     43  Acct-Output-Octets
      16  Login-TCP-Port                    44  Acct-Session-Id
      17  (unassigned)                      45  Acct-Authentic
      18  Reply-Message                     46  Acct-Session-Time
      19  Callback-Number                   47  Acct-Input-Packets
      20  Callback-Id                       48  Acct-Output-Packets
      21  (unassigned)                      49  Acct-Terminate-Cause
      22  Framed-Route                      50  Acct-Multi-Session-Id
      23  Framed-IPX-Network                51  Acct-Link-Count
      24  State
      25  Class                          RADIUS Extension Attributes
      26  Vendor-Specific                [RAD-EXT]
      27  Session-Timeout
      28  Idle-Timeout                      52  Acct-Input-Gigawords



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      29  Termination-Action                53  Acct-Output-Gigawords
      30  Called-Station-Id                 54  Unused
      31  Calling-Station-Id                55  Event-Timestamp
      32  NAS-Identifier
      33  Proxy-State                       70  ARAP-Password
      34  Login-LAT-Service                 71  ARAP-Features
      35  Login-LAT-Node                    72  ARAP-Zone-Access
      73  ARAP-Security
      74  ARAP-Security-Data
      75  Password-Retry
      76  Prompt
      77  Connect-Info
      78  Configuration-Token
      79  EAP-Message
      80  Message-Authenticator

      84  ARAP-Challenge-Response
      85  Acct-Interim-Interval
      87  NAS-Port-Id
      88  Framed-Pool

   RADIUS Tunneling Attributes
   [RAD-TACC]

      64  Tunnel-Type
      65  Tunnel-Medium-Type
      66  Tunnel-Client-Endpoint
      67  Tunnel-Server-Endpoint
      68  Acct-Tunnel-Connection
      69  Tunnel-Password

      81  Tunnel-Private-Group-ID
      82  Tunnel-Assignment-ID
      83  Tunnel-Preference

      90  Tunnel-Client-Auth-ID
      91  Tunnel-Server-Auth-ID

4.2.  DIAMETER

   The DIAMETER framework [DIAM-FRAM] defines a policy protocol used by
   clients to perform Policy, AAA and Resource Control.  This allows a
   single server to handle policies for many services.  The DIAMETER
   protocol consists of a header followed by objects.  Each object is
   encapsulated in a header known as an Attribute-Value Pair (AVP).






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