\" IETF standard document format \" Process with nroff and MS macros \" .pl 10.0i \" page length .po 0 \" page offset .ll 7.2i \" line length .lt 7.2i \" title length .nr LL 7.2i \" set MS line length .nr LT 7.2i \" set MS title length .nr HY 0 \" turn off MS hyphenation \" Running header .ds LH INTERNET-DRAFT .ds CH Diameter NAS Application .ds RH Jun 2004 \" Running footer .ds LF Calhoun et al. .ds CF Expires Jan 2005 .ds RF FORMFEED[Page %] .nh \" base hyphenation off .ad l \" adjust text for ragged right .ls 1 \" single space .tl 'AAA Working Group''Pat R. Calhoun' .tl 'Internet-Draft''Airespace Inc.' .tl 'Category: Standards Track''Glen Zorn' .tl '''Cisco Systems Inc.' .tl '''David Spence' .tl .tl '''David Mitton' .tl '''Circular Networks' .sp .tl '''Jul 2004' .fi .sp .ce Diameter Network Access Server Application .ce draft-ietf-aaa-diameter-nasreq-17.txt .sp .SH Status of this Memo .LP .in 3 This document is an Internet-Draft and is in full conformance with all provisions of Section 3 of RFC3667. .sp By submitting this Internet-Draft, I certify that any applicable patent or other IPR claims of which I am aware have been disclosed, and any of which I become aware will be disclosed, in accordance with RFC 3668. .sp Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. .sp Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." .sp The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. .sp This document is a product of the Authentication, Authorization and Accounting (AAA) Working Group of the Internet Engineering Task Force (IETF). Comments are welcome should be submitted to the mailing list aaa-wg@merit.edu. .sp Copyright (C) The Internet Society 2004. .sp .bp .SH Abstract .LP .in 3 This document describes the Diameter protocol application used for Authentication, Authorization and Accounting (AAA) services in the Network Access Server (NAS) environment. This application specification, when combined with the Diameter Base protocol, Transport Profile, and Extensible Authentication Protocol specifications, satisfies typical network access services requirements. .sp Initial deployments of the Diameter protocol are expected to include legacy systems. Therefore, this application was carefully designed to ease the burden of protocol conversion between RADIUS and Diameter. This is achieved by including the RADIUS attribute space, and eliminating the need to perform many attribute translations. .sp The interactions between Diameter applications and RADIUS specified in this document are to be applied to all Diameter applications. In this sense, this document extends the Base Diameter protocol. .bp .SH Table of Contents .LP TOC Placeholder page1 .bp .LP TOC Placeholder p2 .bp .LP TOC Placeholder p3 .bp .LP TOC Placeholder p4 .bp .NH 1 Introduction .XS \*(SN Introduction .XE .LP .in 3 This document describes the Diameter protocol application used for AAA in the Network Access Server (NAS) environment. This Diameter NAS application specification, when combined with the Diameter Base protocol [Base], Transport Profile [DiamTrans], and EAP [DiamEAP] specifications, satisfies NAS-related requirements defined in RFC2989 [AAACriteria] and RFC3169 [NASCriteria]. .sp Initial deployments of the Diameter protocol are expected to include legacy systems. Therefore, this application was carefully designed to ease the burden of protocol conversion between RADIUS and Diameter. This is achieved by including the RADIUS attribute space, and eliminating the need to perform many attribute translations. .sp The interactions between Diameter applications and RADIUS specified in this document are to be applied to all Diameter applications. In this sense, this document extends the Base Diameter protocol [Base]. .sp This document first describes the operation of a Diameter NAS application. Then it defines the Diameter message Command-Codes. The following sections enumerate the AVPs used in these messages grouped by common usage. These are session identification, authentication, authorization, tunneling, and accounting. The authorization AVPs are further broken down by service type. Interaction and backwards compatibility issues with RADIUS are discussed in later sections. .sp .NH 2 Terminology .XS \*(SN Terminology .XE .LP .in 3 The base Diameter [Base] specification Section 1.4 defines most of the terminology used in this document. Additionally, the following terms and acronyms are used in this application: .sp NAS - Network Access Server; a device which provides an access service for a user to a network. The service may be a network connection, or a value added service such as terminal emulation. [NASmodel] PPP - Point-to-Point Protocol; a multiprotocol serial datalink. PPP is the primary IP datalink used for dial-in NAS connection service. [PPP] CHAP - Challenge Handshake Authentication Protocol; an authentication process used in PPP. [PPPCHAP] PAP - Password Authentication Protocol; a deprecated PPP authentication process, but often used for backwards compatibility [PAP]. SLIP - Serial Line Interface Protocol; a serial datalink that only supports IP. An earlier design, prior to PPP. ARAP - Appletalk Remote Access Protocol; a serial datalink for accessing Appletalk networks [ARAP]. IPX - Internet Packet Exchange; The network protocol used by NetWare networks [IPX]. LAT - Local Area Transport; A Digital Equipment Corp. LAN protocol for terminal services [LAT]. VPN - Virtual Private Network; in this document it is used to describe access services which use tunneling methods. .sp .NH 2 Requirements Language .XS \*(SN Requirements Language .XE .LP .in 3 In this document, the key words "MAY", "MUST", "MUST NOT", "OPTIONAL", "RECOMMENDED", "SHOULD", and "SHOULD NOT", are to be interpreted as described in [Keywords]. .sp .NH 2 Advertising Application Support .XS \*(SN Advertising Application Support .XE .LP .in 3 Diameter applications conforming to this specification MUST advertise support by including the value of one (1) in the Auth-Application-Id of Capabilities-Exchange-Request (CER), AA-Request (AAR) and AA-Answer (AAA) messages. All other messages are defined by [Base] and use the Base application id value. .sp .NH 1 NAS Calls, Ports, and Sessions .XS \*(SN NAS Calls, Ports, and Sessions .XE .LP .in 3 The arrival of a new call or service connection at a port of a Network Access Server (NAS) starts a Diameter NAS message exchange. Information about the call, the identity of the user, and the user's authentication information are packaged into a Diameter AA-Request (AAR) message and sent to a server. .sp The server processes the information and responds with a Diameter AA-Answer (AAA) message which contains authorization information for the NAS, or a failure code (Result-Code AVP). If the value of Result-Code is DIAMETER_MULTI_ROUND_AUTH, an additional authentication exchange is indicated, and several AAR and AAA messages may be exchanged until the transaction completes. .sp The Diameter protocol allows authorization-only requests depending on the Auth-Request-Type AVP, where no authentication information is contained in a request from the client. This capability goes beyond the Call Check capabilities described in Section 5.6 of [RADIUS] in that no access decision is requested. As a result, service cannot be started as a result of a response to an authorization-only request without introducing a significant security vulnerability. .sp Since no equivalent capability exists in RADIUS, authorization-only requests from a NAS implementing Diameter may not be easily translated to an equivalent RADIUS message by a Diameter/RADIUS gateway. For example, where a Diameter authorization-only request cannot be translated to a RADIUS Call Check, it would be necessary for the Diameter/RADIUS gateway to add authentication information to the RADIUS Access Request. On receiving the Access-Reply, the Diameter/RADIUS gateway would need to discard the access decision (Accept/Reject). It is not clear that these translations can be accomplished without adding significant security vulnerabilities. .NH 2 Diameter Session Establishment .XS \*(SN Diameter Session Establishment .XE .LP .in 3 When the authentication or authorization exchange completes successfully, the NAS application SHOULD start a session context. If the Result-Code of DIAMETER_MULTI_ROUND_AUTH is returned, the exchange continues until a success or error is returned. .sp If accounting is active, the application MUST also send an Accounting message [Base]. An Accounting-Record-Type of START_RECORD, is sent for a new session. If a session fails to start, the type EVENT_RECORD message with the reason for the failure described is sent. .sp Note that the return of an unsupportable Accounting-Realtime-Required value [Base] would result in a failure to establish the session. .sp .in 0 .NH 2 Diameter Session Reauthentication or Reauthorization .XS \*(SN Diameter Session Reauthentication or Reauthorization .XE .LP .in 3 .sp The Diameter Base protocol allows for users to be periodically reauthenticated and/or reauthorized. In such instances, the Session-Id AVP in the AAR message MUST be the same as the one present in the original authentication/authorization message. .sp A Diameter server informs the NAS of the maximum time allowed before reauthentication or reauthorization via the Authorization-Lifetime AVP [Base]. A NAS MAY reauthenticate and/or reauthorize before the end, but A NAS MUST reauthenticate and/or reauthorize at the end of the period provided by the Authorization-Lifetime AVP. The failure of a reauthentication exchange will cause the service to be terminated. .sp Furthermore, it is possible for Diameter servers to issue an unsolicited reauthentication and/or reauthorization requests (e.g. Re-Auth-Request (RAR) message [Base]) to the NAS. Upon receipt of such a message, the NAS MUST respond to the request with a Re-Auth-Answer (RAA) message [Base]. .sp If the RAR properly identifies an active session, the NAS will initiate a new local reauthentication or authorization sequence as indicated by the Re-Auth-Request-Type value. This will cause the NAS to send a new AAR message using the existing Session-Id. The server will respond with an AAA message to specify the new service parameters. .sp If accounting is active, every change of authentication or authorization SHOULD generate an accounting message. If the NAS service is a continuation of the prior user context, then an Accounting-Record-Type of INTERIM_RECORD indicating the new session attributes and cumulative status would be appropriate. If a new user or a significant change in authorization is detected by the NAS, then the service may consider it appropriate to send two messages of the types STOP_RECORD, and START_RECORD. Accounting may change the subsession identifiers (Acct-Session-ID, or Acct-Sub-Session-Id) to indicate such sub-sessions. A service may also use a different Session-Id value for accounting (See [BASE] Section 9.6). .sp However, the Diameter Session-ID AVP value used for the initial authorization exchange MUST be used to generate an STR message when the session context is terminated. .sp .NH 2 Diameter Session Termination .XS \*(SN Diameter Session Termination .XE .LP .in 3 When a NAS receives an indication that a user's session is being disconnected by the client (e.g. LCP Terminate is received) or administrative command, the NAS MUST issue a Session-Termination-Request (STR) [Base] to its Diameter Server. This will ensure that any resources maintained on the servers are freed appropriately. .sp Furthermore, a NAS that receives a Abort-Session-Request (ASR) [Base] MUST issue an ASA if the session identified is active, and disconnect the PPP (or tunneling) session. .sp Termination of the session context MUST cause the sending of an Accounting STOP_RECORD message [Base], if accounting is active. .sp More information on Diameter Session Termination is in [Base] section 8.4 and 8.5 .in 0 .NH NAS Messages .XS \*(SN NAS Messages .XE .LP .in 3 This section defines the Diameter message Command-Code [Base] values that MUST be supported by all Diameter implementations that conform to this specification. The Command Codes are: .KS .nf .in 6 Command-Name Abbrev. Code Reference ------------------------------------------------------- AA-Request AAR 265 3.1 AA-Answer AAA 265 3.2 Re-Auth-Request RAR 258 3.3 Re-Auth-Answer RAA 258 3.4 Session-Termination-Request STR 275 3.5 Session-Termination-Answer STA 275 3.6 Abort-Session-Request ASR 274 3.7 Abort-Session-Answer ASA 274 3.8 Accounting-Request ACR 271 3.9 Accounting-Answer ACA 271 3.10 .fi .KE .sp .NH 2 AA-Request (AAR) Command .XS \*(SN AA-Request (AAR) Command .XE .LP .in 3 The AA-Request message (AAR), indicated by the Command-Code field set to 265 and the 'R' bit set in the Command Flags field, is used in order to request authentication and/or authorization for a given NAS user. The type of request is identified through the Auth-Request-Type AVP [Base]. The recommended value for most RADIUS interoperabily situations, is AUTHORIZE_AUTHENTICATE. .sp If Authentication is requested the User-Name attribute SHOULD be present, as well as any additional authentication AVPs that would carry the password information. A request for authorization only SHOULD include the information from which the authorization will be performed, such as the User-Name, Called-Station-Id, or Calling-Station-Id AVPs. All requests SHOULD contain AVPs uniquely identifying the source of the call, such as Origin-Host, and NAS-Port. Certain networks MAY use different AVPs for authorization purposes. A request for authorization will include some AVPs defined in section 6. .sp It is possible for a single session to be authorized first, then followed by an authentication request. .sp This AA-Request message MAY be the result of a multi-round authentication exchange, which occurs when the AA-Answer message is received with the Result-Code AVP set to DIAMETER_MULTI_ROUND_AUTH. A subsequent AAR message SHOULD be sent, with the User-Password AVP that includes the user's response to the prompt, and MUST include any State AVPs that were present in the AAA message. .sp .in 3 Message Format .sp .in 6 .nf ::= < Diameter Header: 265, REQ, PXY > < Session-Id > { Auth-Application-Id } { Origin-Host } { Origin-Realm } { Destination-Realm } { Auth-Request-Type } [ Destination-Host ] [ NAS-Identifier ] [ NAS-IP-Address ] [ NAS-IPv6-Address ] [ NAS-Port ] [ NAS-Port-Id ] [ NAS-Port-Type ] [ Origin-State-Id ] [ Port-Limit ] [ User-Name ] [ User-Password ] [ Service-Type ] [ State ] [ Authorization-Lifetime ] [ Auth-Grace-Period ] [ Auth-Session-State ] [ Callback-Number ] [ Called-Station-Id ] [ Calling-Station-Id ] [ Originating-Line-Info ] [ Connect-Info ] [ CHAP-Auth ] [ CHAP-Challenge ] * [ Framed-Compression ] [ Framed-Interface-Id ] [ Framed-IP-Address ] * [ Framed-IPv6-Prefix ] [ Framed-IP-Netmask ] [ Framed-MTU ] [ Framed-Protocol ] [ ARAP-Password ] [ ARAP-Security ] * [ ARAP-Security-Data ] * [ Login-IP-Host ] * [ Login-IPv6-Host ] [ Login-LAT-Group ] [ Login-LAT-Node ] [ Login-LAT-Port ] [ Login-LAT-Service ] * [ Tunneling ] * [ Proxy-Info ] * [ Route-Record ] * [ AVP ] .fi .sp .NH 2 AA-Answer (AAA) Command .XS \*(SN AA-Answer (AAA) Command .XE .LP .in 3 The AA-Answer (AAA) message, is indicated by the Command-Code field set to 265 and the 'R' bit cleared in the Command Flags field, is sent in response to the AA-Request message. If authorization was requested, a successful response will include the authorization AVPs appropriate for the service being provided, as defined in section 6. .sp For authentication exchanges that require more than a single round trip, the server MUST set the Result-Code AVP to DIAMETER_MULTI_ROUND_AUTH. An AAA message with this result code MAY include one or more Reply-Message and MAY include zero or one State AVPs. .sp If the Reply-Message AVP was present, the network access server SHOULD send the text to the user's client for display to the user, instructing it to prompt the user for a response. For example, this capability can be achieved in PPP via PAP. If the access client is unable to prompt the user for a new response, it MUST treat the AA-Answer with the Reply-Message AVP as an error, and deny access. .sp .in 3 Message Format .sp .in 6 .KS .nf ::= < Diameter Header: 265, PXY > < Session-Id > { Auth-Application-Id } { Auth-Request-Type } { Result-Code } { Origin-Host } { Origin-Realm } [ User-Name ] [ Service-Type ] * [ Class ] * [ Configuration-Token ] [ Acct-Interim-Interval ] [ Error-Message ] [ Error-Reporting-Host ] * [ Failed-AVP ] [ Idle-Timeout ] [ Authorization-Lifetime ] [ Auth-Grace-Period ] [ Auth-Session-State ] [ Re-Auth-Request-Type ] [ Session-Timeout ] [ State ] * [ Reply-Message ] [ Origin-State-Id ] * [ Filter-Id ] [ Password-Retry ] [ Port-Limit ] [ Prompt ] [ ARAP-Challenge-Response ] [ ARAP-Features ] [ ARAP-Security ] * [ ARAP-Security-Data ] [ ARAP-Zone-Access ] [ Callback-Id ] [ Callback-Number ] [ Framed-Appletalk-Link ] * [ Framed-Appletalk-Network ] [ Framed-Appletalk-Zone ] * [ Framed-Compression ] [ Framed-Interface-Id ] [ Framed-IP-Address ] * [ Framed-IPv6-Prefix ] [ Framed-IPv6-Pool ] * [ Framed-IPv6-Route ] [ Framed-IP-Netmask ] * [ Framed-Route ] [ Framed-Pool ] [ Framed-IPX-Network ] [ Framed-MTU ] [ Framed-Protocol ] [ Framed-Routing ] * [ Login-IP-Host ] * [ Login-IPv6-Host ] [ Login-LAT-Group ] [ Login-LAT-Node ] [ Login-LAT-Port ] [ Login-LAT-Service ] [ Login-Service ] [ Login-TCP-Port ] * [ NAS-Filter-Rule ] * [ QoS-Filter-Rule ] * [ Tunneling ] * [ Redirect-Host ] [ Redirect-Host-Usage ] [ Redirect-Max-Cache-Time ] * [ Proxy-Info ] * [ AVP ] .fi .KE .in 0 .sp .NH 2 Re-Auth-Request (RAR) Command .XS \*(SN Re-Auth-Request (RAR) Command .XE .LP .in 3 A Diameter server may initiate a re-authentication and/or re- authorization service for a particular session by issuing a Re-Auth- Request (RAR) message [Base]. .sp For example, for pre-paid services, the Diameter server that originally authorized a session may need some confirmation that the user is still using the services. .sp A NAS that receives a RAR message with Session-Id equal to a currently active session and a Re-Auth-Type that includes authentication, MUST initiate a re-authentication towards the user, if the service supports this particular feature. .sp .in 3 Message Format .sp .in 6 .nf ::= < Diameter Header: 258, REQ, PXY > < Session-Id > { Origin-Host } { Origin-Realm } { Destination-Realm } { Destination-Host } { Auth-Application-Id } { Re-Auth-Request-Type } [ User-Name ] [ Origin-State-Id ] [ NAS-Identifier ] [ NAS-IP-Address ] [ NAS-IPv6-Address ] [ NAS-Port ] [ NAS-Port-Id ] [ NAS-Port-Type ] [ Service-Type ] [ Framed-IP-Address ] [ Framed-IPv6-Prefix ] [ Framed-Interface-Id ] [ Called-Station-Id ] [ Calling-Station-Id ] [ Originating-Line-Info ] [ Acct-Session-Id ] [ Acct-Multi-Session-Id ] [ State ] * [ Class ] [ Reply-Message ] * [ Proxy-Info ] * [ Route-Record ] * [ AVP ] .fi .in 0 .sp .NH 2 Re-Auth-Answer (RAA) Command .XS \*(SN Re-Auth-Answer (RAA) Command .XE .LP .in 3 The Re-Auth-Answer (RAA) message [Base], is sent in response to the RAR. The Result-Code AVP MUST be present, and indicates the disposition of the request. .sp A successful RAA transaction MUST be followed by an AA-Request message. .sp .in 3 Message Format .sp .in 6 .nf .KS ::= < Diameter Header: 258, PXY > < Session-Id > { Result-Code } { Origin-Host } { Origin-Realm } [ User-Name ] [ Origin-State-Id ] [ Error-Message ] [ Error-Reporting-Host ] * [ Failed-AVP ] * [ Redirected-Host ] [ Redirected-Host-Usage ] [ Redirected-Host-Cache-Time ] [ Service-Type ] * [ Configuration-Token ] [ Idle-Timeout ] [ Authorization-Lifetime ] [ Auth-Grace-Period ] [ Re-Auth-Request-Type ] [ State ] * [ Class ] * [ Reply-Message ] [ Prompt ] * [ Proxy-Info ] * [ AVP ] .KE .fi .in 0 .sp .NH 2 Session-Termination-Request (STR) Command .XS \*(SN Session-Termination-Request (STR) Command .XE .LP .in 3 The Session-Termination-Request (STR) message [Base] is sent by the NAS to inform the Diameter Server that an authenticated and/or authorized session is being terminated. .sp .in 3 Message Format .sp .in 6 .nf ::= < Diameter Header: 275, REQ, PXY > < Session-Id > { Origin-Host } { Origin-Realm } { Destination-Realm } { Auth-Application-Id } { Termination-Cause } [ User-Name ] [ Destination-Host ] * [ Class ] [ Origin-State-Id ] * [ Proxy-Info ] * [ Route-Record ] * [ AVP ] .fi .in 0 .sp .NH 2 Session-Termination-Answer (STA) Command .XS \*(SN Session-Termination-Answer (STA) Command .XE .LP .in 3 The Session-Termination-Answer (STA) message [Base] is sent by the Diameter Server to acknowledge the notification that the session has been terminated. The Result-Code AVP MUST be present, and MAY contain an indication that an error occurred while servicing the STR. .sp Upon sending or receipt of the STA, the Diameter Server MUST release all resources for the session indicated by the Session-Id AVP. Any intermediate server in the Proxy-Chain MAY also release any resources, if necessary. .sp .in 3 Message Format .sp .in 6 .nf ::= < Diameter Header: 275, PXY > < Session-Id > { Result-Code } { Origin-Host } { Origin-Realm } [ User-Name ] * [ Class ] [ Error-Message ] [ Error-Reporting-Host ] * [ Failed-AVP ] [ Origin-State-Id ] * [ Redirect-Host ] [ Redirect-Host-Usase ] [ Redirect-Max-Cache-Time ] * [ Proxy-Info ] * [ AVP ] .fi .in 0 .sp .NH 2 Abort-Session-Request (ASR) Command .XS \*(SN Abort-Session-Request (ASR) Command .XE .LP .in 3 The Abort-Session-Request (ASR) message [Base], may be sent by any server to the NAS that is providing session service, to request that the session identified by the Session-Id be stopped. .sp .in 3 Message Format .sp .in 6 .nf .KS ::= < Diameter Header: 274, REQ, PXY > < Session-Id > { Origin-Host } { Origin-Realm } { Destination-Realm } { Destination-Host } { Auth-Application-Id } [ User-Name ] [ Origin-State-Id ] [ NAS-Identifier ] [ NAS-IP-Address ] [ NAS-IPv6-Address ] [ NAS-Port ] [ NAS-Port-Id ] [ NAS-Port-Type ] [ Service-Type ] [ Framed-IP-Address ] [ Framed-IPv6-Prefix ] [ Framed-Interface-Id ] [ Called-Station-Id ] [ Calling-Station-Id ] [ Originating-Line-Info ] [ Acct-Session-Id ] [ Acct-Multi-Session-Id ] [ State ] * [ Class ] * [ Reply-Message ] * [ Proxy-Info ] * [ Route-Record ] * [ AVP ] .KE .fi .NH 2 Abort-Session-Answer (ASA) Command .XS \*(SN Abort-Session-Answer (ASA) Command .XE .LP .in 3 The Abort-Session-Answer (ASA) message [Base], is sent in response to the ASR. The Result-Code AVP MUST be present, and indicates the disposition of the request. .sp If the session identified by Session-Id in the ASR was successfully terminated, Result-Code is set to DIAMETER_SUCCESS. If the session is not currently active, Result-Code is set to DIAMETER_UNKNOWN_SESSION_ID. If the access device does not stop the session for any other reason, Result-Code is set to DIAMETER_UNABLE_TO_COMPLY. .sp .in 3 Message Format .sp .in 6 .nf ::= < Diameter Header: 274, PXY > < Session-Id > { Result-Code } { Origin-Host } { Origin-Realm } [ User-Name ] [ Origin-State-Id ] [ State] [ Error-Message ] [ Error-Reporting-Host ] * [ Failed-AVP ] * [ Redirected-Host ] [ Redirected-Host-Usage ] [ Redirected-Max-Cache-Time ] * [ Proxy-Info ] * [ AVP ] .fi .in 0 .NH 2 Accounting-Request (ACR) Command .XS \*(SN Accounting-Request (ACR) Command .XE .LP .in 3 The Accounting-Request (ACR) message [Base], is sent by the NAS, to report it's session information to a target server downstream. .sp One of Acct-Application-Id and Vendor-Specific-Application-Id AVPs MUST be present. If the Vendor-Specific-Application-Id grouped AVP is present, it must have an Acct-Application-Id inside. .sp The AVPs listed in the Base MUST be assumed to be present as approriate. NAS service specific accounting AVPs, SHOULD be present as described in section 8 and the rest of this specification. .sp .in 3 Message Format .sp .in 6 .nf .KS ::= < Diameter Header: 271, REQ, PXY > < Session-Id > { Origin-Host } { Origin-Realm } { Destination-Realm } { Accounting-Record-Type } { Accounting-Record-Number } [ Acct-Application-Id ] [ Vendor-Specific-Application-Id ] [ User-Name ] [ Accounting-Sub-Session-Id ] [ Acct-Session-Id ] [ Acct-Multi-Session-Id ] [ Origin-State-Id ] [ Destination-Host ] [ Event-Timestamp ] [ Acct-Delay-Time ] [ NAS-Identifier ] [ NAS-IP-Address ] [ NAS-IPv6-Address ] [ NAS-Port ] [ NAS-Port-Id ] [ NAS-Port-Type ] * [ Class ] [ Service-Type ] [ Termination-Cause ] [ Accounting-Input-Octets ] [ Accounting-Input-Packets ] [ Accounting-Output-Octets ] [ Accounting-Output-Packets ] [ Acct-Authentic ] [ Accounting-Auth-Method ] [ Acct-Link-Count ] [ Acct-Session-Time ] [ Acct-Tunnel-Connection ] [ Acct-Tunnel-Packets-Lost ] [ Callback-Id ] [ Callback-Number ] [ Called-Station-Id ] [ Calling-Station-Id ] * [ Connection-Info ] [ Originating-Line-Info ] [ Authorization-Lifetime ] [ Session-Timeout ] [ Idle-Timeout ] [ Port-Limit ] [ Accounting-Realtime-Required ] [ Acct-Interim-Interval ] * [ Filter-Id ] * [ NAS-Filter-Rule ] * [ Qos-Filter-Rule ] [ Framed-AppleTalk-Link ] [ Framed-AppleTalk-Network ] [ Framed-AppleTalk-Zone ] [ Framed-Compression ] [ Framed-Interface-Id ] [ Framed-IP-Address ] [ Framed-IP-Netmask ] * [ Framed-IPv6-Prefix ] [ Framed-IPv6-Pool ] * [ Framed-IPv6-Route ] [ Framed-IPX-Network ] [ Framed-MTU ] [ Framed-Pool ] [ Framed-Protocol ] * [ Framed-Route ] [ Framed-Routing ] * [ Login-IP-Host ] * [ Login-IPv6-Host ] [ Login-LAT-Group ] [ Login-LAT-Node ] [ Login-LAT-Port ] [ Login-LAT-Service ] [ Login-Service ] [ Login-TCP-Port ] * [ Tunneling ] * [ Proxy-Info ] * [ Route-Record ] * [ AVP ] .KE .fi .in 0 .sp .NH 2 Accounting-Answer (ACA) Command .XS \*(SN Accounting-Answer (ACA) Command .XE .LP .in 3 The Accounting-Answer (ACA) message [Base], is used to acknowledge an Accounting-Request command. The Accounting-Answer command contains the same Session-Id as the Request. If the Accounting- Request was protected by end-to-end security, then the corresponding ACA message MUST be protected by end-to-end security. .sp Only the target Diameter Server, or home Diameter Server, SHOULD respond with the Accounting-Answer command. .sp One of Acct-Application-Id and Vendor-Specific-Application-Id AVPs MUST be present, as was in the request. .sp The AVPs listed in the Base MUST be assumed to be present as approriate. NAS service specific accounting AVPs, SHOULD be present as described in section 8 and the rest of this specification. .sp .in 3 Message Format .sp .in 6 .nf .KS ::= < Diameter Header: 271, PXY > < Session-Id > { Result-Code } { Origin-Host } { Origin-Realm } { Accounting-Record-Type } { Accounting-Record-Number } [ Acct-Application-Id ] [ Vendor-Specific-Application-Id ] [ User-Name ] [ Accounting-Sub-Session-Id ] [ Acct-Session-Id ] [ Acct-Multi-Session-Id ] [ Event-Timestamp ] [ Error-Message ] [ Error-Reporting-Host ] * [ Failed-AVP ] [ Origin-State-Id ] [ NAS-Identifier ] [ NAS-IP-Address ] [ NAS-IPv6-Address ] [ NAS-Port ] [ NAS-Port-Id ] [ NAS-Port-Type ] [ Service-Type ] [ Termination-Cause ] [ Accounting-Realtime-Required ] [ Acct-Interim-Interval ] * [ Class ] * [ Proxy-Info ] * [ Route-Record ] * [ AVP ] .KE .fi .in 0 .sp .NH 1 NAS Session AVPs .XS \*(SN NAS Session AVPs .XE .LP .in 3 Diameter reserves the AVP Codes 0-255 for RADIUS functions that are implemented in Diameter. .sp AVPs new to Diameter have code values 256 and greater. A Diameter message that includes one of these AVPs may represent functions not present in the RADIUS environment and may cause interoperability issues should the request traverse a AAA system that only supports the RADIUS protocol. .sp There are some RADIUS attributes that are not allowed or supported directly in Diameter. See section 9 below for more information. .in 0 .sp .NH 2 Call and Session Information .XS \*(SN Call and Session Information .XE .LP .in 3 This section contains the AVPs specific to NAS Diameter applications that are needed to identify the call and session context and status information. On a request, this information allows the server to qualify the session. .sp These AVPs are used in addition to the Base AVPs of: .nf .in 6 Session-Id Auth-Application-Id Origin-Host Origin-Realm Auth-Request-Type Termination-Cause .in 3 .fi .sp The following table describes the Session level AVPs, their AVP Code values, types, possible flag values and whether the AVP MAY be encrypted. .KS .nf .in 3 +---------------------+ | AVP Flag rules | |----+-----+----+-----|----+ AVP Section | | |SHLD| MUST| | Attribute Name Code Defined Value Type |MUST| MAY | NOT| NOT|Encr| -----------------------------------------|----+-----+----+-----|----| NAS-Port 5 4.2 Unsigned32 | M | P | | V | Y | NAS-Port-Id 87 4.3 UTF8String | M | P | | V | Y | NAS-Port-Type 61 4.4 Enumerated | M | P | | V | Y | Called-Station-Id 30 4.5 UTF8String | M | P | | V | Y | Calling-Station- 31 4.6 UTF8String | M | P | | V | Y | Id | | | | | | Connect-Info 77 4.7 UTF8String | M | P | | V | Y | Originating-Line- 94 4.8 OctetString| | M,P | | V | Y | Info | | | | | | Reply-Message 18 4.9 UTF8String | M | P | | V | Y | -----------------------------------------|----+-----+----+-----|----| .fi .KE .NH 2 NAS-Port AVP .XS \*(SN NAS-Port AVP .XE .LP .in 3 The NAS-Port AVP (AVP Code 5) is of type Unsigned32 and contains the physical or virtual port number of the NAS which is authenticating the user. Note that this is using "port" in its sense of a service connection on the NAS, not in the sense of an IP protocol identifier. .sp Either NAS-Port or NAS-Port-Id (AVP Code 87) SHOULD be present in AA-Request commands if the NAS differentiates among its ports. .sp .in 0 .NH 2 NAS-Port-Id AVP .XS \*(SN NAS-Port-Id AVP .XE .LP .in 3 The NAS-Port-Id AVP (AVP Code 87) is of type UTF8String and consists of ASCII text that identifies the port of the NAS which is authenticating the user. Note that this is using "port" in its sense of a service connection on the NAS, not in the sense of an IP protocol identifier. .sp Either NAS-Port or NAS-Port-Id SHOULD be present in AA-Request commands if the NAS differentiates among its ports. NAS-Port-Id is intended for use by NASes which cannot conveniently number their ports. .sp .NH 2 NAS-Port-Type AVP .XS \*(SN NAS-Port-Type AVP .XE .LP .in 3 The NAS-Port-Type AVP (AVP Code 61) is of type Enumerated and contains the type of the port on which the NAS is authenticating the user. This AVP SHOULD be present if the NAS uses the same NAS-Port number ranges for different service types concurrently. .sp The supported values are defined in [RADIUSTypes]. The following list is informational and subject to change in the IANA. .sp .nf 0 Async 1 Sync 2 ISDN Sync 3 ISDN Async V.120 4 ISDN Async V.110 5 Virtual 6 PIAFS 7 HDLC Clear Channel 8 X.25 9 X.75 10 G.3 Fax 11 SDSL - Symmetric DSL 12 ADSL-CAP - Asymmetric DSL, Carrierless Amplitude Phase Modulation 13 ADSL-DMT - Asymmetric DSL, Discrete Multi-Tone 14 IDSL - ISDN Digital Subscriber Line 15 Ethernet 16 xDSL - Digital Subscriber Line of unknown type 17 Cable 18 Wireless - Other 19 Wireless - IEEE 802.11 20 Token-Ring [RAD802.1X] 21 FDDI [RAD802.1X] 22 Wireless - CDMA2000 23 Wireless - UMTS 24 Wireless - 1X-EV 25 IAPP [IEEE 802.11f] .fi .sp .NH 2 Called-Station-Id AVP .XS \*(SN Called-Station-Id AVP .XE .LP .in 3 The Called-Station-Id AVP (AVP Code 30) is of type UTF8String, and allows the NAS to send in the request, the ASCII string describing the layer 2 address that the user contacted to. For dialup access, this can be a phone number, obtained using Dialed Number Identification (DNIS) or a similar technology. Note that this may be different from the phone number the call comes in on. For use with IEEE 802 access, the Called-Station-Id MAY contain a MAC address, formatted as described in [RAD802.1X]. It SHOULD only be present in authentication and/or authorization requests. .sp If the Auth-Request-Type AVP is set to authorization-only and the User-Name AVP is absent, the Diameter Server MAY perform authorization based on this field. This can be used by a NAS to request whether a call should be answered based on the DNIS. .sp The codification of the range of allowed usage of this field is outside the scope of this specification. .sp .NH 2 Calling-Station-Id AVP .XS \*(SN Calling-Station-Id AVP .XE .LP .in 3 The Calling-Station-Id AVP (AVP Code 31) is of type UTF8String, and allows the NAS to send in the request the ASCII string describing the layer 2 address that the user connected from. For dialup access, this is the phone number that the call came from, using Automatic Number Identification (ANI) or a similar technology. For use with IEEE 802 access, the Calling-Station-Id AVP MAY contain a MAC address, formated as described in [RAD802.1X]. It SHOULD only be present in authentication and/or authorization requests. .sp If the Auth-Request-Type AVP is set to authorization-only and the User-Name AVP is absent, the Diameter Server MAY perform authorization based on this field. This can be used by a NAS to request whether a call should be answered based on the layer 2 address (ANI, MAC Address, etc.) .sp The codification of the range of allowed usage of this field is outside the scope of this specification. .sp .NH 2 Connect-Info AVP .XS \*(SN Connect-Info AVP .XE .LP .in 3 The Connect-Info AVP (AVP Code 77) is of type UTF8String and is sent in the AA-Request message or ACR STOP message. When sent in the Access-Request it indicates the nature of the user's connection. The connection speed SHOULD be included at the beginning of the first Connect-Info AVP in the message. If the transmit and receive connection speeds differ, they may both be included in the first AVP with the transmit speed first (the speed the NAS modem transmits at), a slash (/), the receive speed, then optionally other information. .sp For example, "28800 V42BIS/LAPM" or "52000/31200 V90" .sp More than one Connect-Info attribute may be present in an Accounting-Request packet to accommodate expected efforts by ITU to have modems report more connection information in a standard format that might exceed 252 octets. .sp If sent in the ACR STOP, this attribute may be used to summarize statistics relating to session quality. For example, in IEEE 802.11, the Connect-Info attribute may contain information on the number of link layer retransmissions. The exact format of this attribute is implementation specific. .sp .NH 2 Originating-Line-Info AVP .XS \*(SN Originating-Line-Info AVP .XE .LP .in 3 The Originating-Line-Info AVP (AVP Code 94) is of type OctetString and is sent by the NAS system to convey information about the origin of the call from an SS7 system. .sp The originating line information (OLI) information element indicates the nature and/or characteristics of the line from which a call originated (e.g. payphone, hotel, cellular). Telephone companies are starting to offer OLI to their customers as an option over Primary Rate Interface (PRI). Internet Service Providers (ISPs) can use OLI in addition to Called-Station-Id and Calling-Station-Id attributes to differentiate customer calls and define different services .sp The Value field contains two octets (00-99). ANSI T1.113 and BELLCORE 394 can be used for additional information about those values and their use. For more information on current assignment values see [ANITypes]. .sp .nf Value Description ------------------------------------------------------------ 00 Plain Old Telephone Service (POTS) 01 Multiparty line (more than 2) 02 ANI Failure 03 ANI Observed 04 ONI Observed 05 ANI Failure Observed 06 Station Level Rating 07 Special Operator Handling Required 08 InterLATA Restricted 10 Test Call 20 Automatic Identified Outward Dialing (AIOD) 23 Coin or Non-Coin 24 Toll Free Service (Non-Pay origination) 25 Toll Free Service (Pay origination) 27 Toll Free Service (Coin Control origination) 29 Prison/Inmate Service 30-32 Intercept 30 Intercept (blank) 31 Intercept (trouble) 32 Intercept (regular) 34 Telco Operator Handled Call 40-49 Unrestricted Use 52 Outward Wide Area Telecommunications Service (OUTWATS) 60 Telecommunications Relay Service (TRS)(Unrestricted) 61 Cellular/Wireless PCS (Type 1) 62 Cellular/Wireless PCS (Type 2) 63 Cellular/Wireless PCS (Roaming) 66 TRS (Hotel) 67 TRS (Restricted) 70 Pay Station, No coin control 93 Access for private virtual network service .fi .NH 2 Reply-Message AVP .XS \*(SN Reply-Message AVP .XE .LP .in 3 The Reply-Message AVP (AVP Code 18) is of type UTF8String, and contains text which MAY be displayed to the user. When used in an AA-Answer message with a successful Result-Code AVP it is success information. When found in AAA message with a Result-Code other than DIAMETER_SUCCESS, the AVP contains a failure message. .sp The Reply-Message AVP MAY indicate dialog text to prompt the user before another AA-Request attempt. When used in an AA-Answer, with a Result-Code of DIAMETER_MULTI_ROUND_AUTH or in an Re-Auth-Request message, it MAY contain a dialog text to prompt the user for a response. .sp Multiple Reply-Message's MAY be included and if any are displayed, they MUST be displayed in the same order as they appear in the Diameter message. .sp .NH 1 NAS Authentication AVPs .XS \*(SN NAS Authentication AVPs .XE .LP .in 3 This section defines the AVPs that are necessary to carry the authentication information in the Diameter protocol. The functionality defined here provides a RADIUS-like AAA service, over a more reliable and secure transport, as defined in the base protocol [Base]. .sp The following table describes the AVPs, their AVP Code values, types, possible flag values and whether the AVP MAY be encrypted. .sp .nf .KS .in 3 +---------------------+ | AVP Flag rules | |----+-----+----+-----|----+ AVP Section | | |SHLD| MUST| | Attribute Name Code Defined Value Type |MUST| MAY | NOT| NOT|Encr| -----------------------------------------|----+-----+----+-----|----| User-Password 2 5.1 OctetString| M | P | | V | Y | Password-Retry 75 5.2 Unsigned32 | M | P | | V | Y | Prompt 76 5.3 Enumerated | M | P | | V | Y | CHAP-Auth 402 5.4 Grouped | M | P | | V | Y | CHAP-Algorithm 403 5.5 Enumerated | M | P | | V | Y | CHAP-Ident 404 5.6 OctetString| M | P | | V | Y | CHAP-Response 405 5.7 OctetString| M | P | | V | Y | CHAP-Challenge 60 5.8 OctetString| M | P | | V | Y | ARAP-Password 70 5.9 OctetString| M | P | | V | Y | ARAP-Challenge- 84 5.10 OctetString| M | P | | V | Y | Response | | | | | | ARAP-Security 73 5.11 Unsigned32 | M | P | | V | Y | ARAP-Security- 74 5.12 OctetString| M | P | | V | Y | Data | | | | | | -----------------------------------------|----+-----+----+-----|----| .KE .fi .sp .NH 2 User-Password AVP .XS \*(SN User-Password AVP .XE .LP .in 3 The User-Password AVP (AVP Code 2) is of type OctetString and contains the password of the user to be authenticated, or the user's input in a multi-round authentication exchange. .sp The User-Password AVP contains a user password or one-time password and therefore represents sensitive information. As required in [Base], Diameter messages are encrypted using IPsec or TLS. Unless this AVP is used for one-time passwords, the User-Password AVP SHOULD NOT be used in untrusted proxy environments without encrypting it using end-to-end security techniques, such as the proposed CMS Security [DiamCMS]. .sp The clear-text password (prior to encryption) MUST NOT be longer than 128 bytes in length. .in 0 .sp .NH 2 Password-Retry AVP .XS \*(SN Password-Retry AVP .XE .LP .in 3 The Password-Retry AVP (AVP Code 75) is of type Unsigned32 and MAY be included in the AA-Answer if the Result-Code indicates an authentication failure. The value of this AVP indicates how many authentication attempts a user may be permitted before being disconnected. This AVP is primarily intended for use when the Framed-Protocol AVP (see Section 6.10.1) is set to ARAP. .in 0 .sp .NH 2 Prompt AVP .XS \*(SN Prompt AVP .XE .LP .in 3 The Prompt AVP (AVP Code 76) is of type Enumerated, and MAY be present in the AA-Answer message. When present, it is used by the NAS to determine whether the user's response, when entered, should be echoed. .sp The supported values are listed in [RADIUSTypes]. The following list is informational: .nf 0 No Echo 1 Echo .fi .in 0 .sp .NH 2 CHAP-Auth AVP .XS \*(SN CHAP-Auth AVP .XE .LP .in 3 The CHAP-Auth AVP (AVP Code 402) is of type Grouped and contains the information necessary to authenticate a user using the PPP Challenge-Handshake Authentication Protocol (CHAP) [PPPCHAP]. If the CHAP-Auth AVP is found in a message, the CHAP-Challenge AVP MUST be present as well. The optional AVPs containing the CHAP response depend upon the value of the CHAP-Algorithm AVP. The grouped AVP has the following ABNF grammar: .sp .nf .in 6 .KS CHAP-Auth ::= < AVP Header: 402 > { CHAP-Algorithm } { CHAP-Ident } [ CHAP-Response ] * [ AVP ] .fi .KE .in 0 .sp .NH 2 CHAP-Algorithm AVP .XS \*(SN CHAP-Algorithm AVP .XE .LP .in 3 The CHAP-Algorithm AVP (AVP Code 403) is of type Enumerated and contains the algorithm identifier used in the computation of the CHAP response [PPPCHAP]. The following values are currently supported: .sp .in 6 CHAP with MD5 5 .in 9 The CHAP response is computed using the procedure described in [PPPCHAP]. This algorithm requires that CHAP-Response AVP MUST be present in the CHAP-Auth AVP. .in 0 .sp .NH 2 CHAP-Ident AVP .XS \*(SN CHAP-Ident AVP .XE .LP .in 3 The CHAP-Ident AVP (AVP Code 404) is of type OctetString and contains the one octet CHAP Identifier used in the computation of the CHAP response [PPPCHAP]. .in 0 .sp .NH 2 CHAP-Response AVP .XS \*(SN CHAP-Response AVP .XE .LP .in 3 The CHAP-Response AVP (AVP Code 405) is of type OctetString and contains the 16 octet authentication data provided by the user in response to the CHAP challenge [PPPCHAP]. .in 0 .sp .NH 2 CHAP-Challenge AVP .XS \*(SN CHAP-Challenge AVP .XE .LP .in 3 The CHAP-Challenge AVP (AVP Code 60) is of type OctetString and contains the CHAP Challenge sent by the NAS to the CHAP peer [PPPCHAP]. .in 0 .sp .NH 2 ARAP-Password AVP .XS \*(SN ARAP-Password AVP .XE .LP .in 3 The ARAP-Password AVP (AVP Code 70) is of type OctetString and is only present when the Framed-Protocol AVP (see Section 6.10.1) is included in the message and is set to ARAP. This AVP MUST NOT be present if either the User-Password or the CHAP-Auth AVP is present. See [RADIUSExt] for more information on the contents of this AVP. .in 0 .sp .NH 2 ARAP-Challenge-Response AVP .XS \*(SN ARAP-Challenge-Response AVP .XE .LP .in 3 The ARAP-Challenge-Response AVP (AVP Code 84) is of type OctetString and is only present when the Framed-Protocol AVP (see Section 6.10.1) is included in the message and is set to ARAP. This AVP contains an 8 octet response to the dial-in client's challenge. The RADIUS server calculates this value by taking the dial-in client's challenge from the high order 8 octets of the ARAP-Password AVP and performing DES encryption on this value with the authenticating user's password as the key. If the user's password is less than 8 octets in length, the password is padded at the end with NULL octets to a length of 8 before using it as a key. .in 0 .sp .NH 2 ARAP-Security AVP .XS \*(SN ARAP-Security AVP .XE .LP .in 3 The ARAP-Security AVP (AVP Code 73) is of type Unsigned32, and MAY be present in the AA-Answer message if the Framed-Protocol AVP (see Section 6.10.1) is set to the value of ARAP, and the Result-Code AVP is set to DIAMETER_MULTI_ROUND_AUTH. See [RADIUSExt] for more information on the format of this AVP. .in 0 .sp .NH 2 ARAP-Security-Data AVP .XS \*(SN ARAP-Security-Data AVP .XE .LP .in 3 The ARAP-Security AVP (AVP Code 74) is of type OctetString, and MAY be present in the AA-Request or AA-Answer message if the Framed-Protocol AVP is set to the value of ARAP, and the Result-Code AVP is set to DIAMETER_MULTI_ROUND_AUTH. This AVP contains the security module challenge or response associated with the ARAP Security Module specified in ARAP-Security. .in 0 .sp .NH 1 NAS Authorization AVPs .XS \*(SN NAS Authorization AVPs .XE .LP .in 3 This section contains the authorization AVPs that are supported in the NAS Application. The Service-Type AVP SHOULD be present in all messages, and based on its value, additional AVPs defined in this section and section 7 MAY be present. .sp Due to space constraints, the short form IPFltrRule is used to represent IPFilterRule, and QoSFltrRule for QoSFilterRule .nf .in 3 .KS +---------------------+ | AVP Flag rules | |----+-----+----+-----|----+ AVP Section | | |SHLD| MUST| | Attribute Name Code Defined Value Type |MUST| MAY | NOT| NOT|Encr| -----------------------------------------|----+-----+----+-----|----| Service-Type 6 6.1 Enumerated | M | P | | V | Y | Callback-Number 19 6.2 UTF8String | M | P | | V | Y | Callback-Id 20 6.3 UTF8String | M | P | | V | Y | Idle-Timeout 28 6.4 Unsigned32 | M | P | | V | Y | Port-Limit 62 6.5 Unsigned32 | M | P | | V | Y | NAS-Filter-Rule 400 6.6 IPFltrRule | M | P | | V | Y | Filter-Id 11 6.7 UTF8String | M | P | | V | Y | Configuration- 78 6.8 OctetString| M | | | P,V | | Token | | | | | | QoS-Filter-Rule 407 6.9 QoSFltrRule| | | | | | Framed-Protocol 7 6.10.1 Enumerated | M | P | | V | Y | Framed-Routing 10 6.10.2 Enumerated | M | P | | V | Y | Framed-MTU 12 6.10.3 Unsigned32 | M | P | | V | Y | Framed- 13 6.10.4 Enumerated | M | P | | V | Y | Compression | | | | | | Framed-IP-Address 8 6.11.1 OctetString| M | P | | V | Y | Framed-IP-Netmask 9 6.11.2 OctetString| M | P | | V | Y | Framed-Route 22 6.11.3 UTF8String | M | P | | V | Y | Framed-Pool 88 6.11.4 OctetString| M | P | | V | Y | Framed- 96 6.11.5 Unsigned64 | M | P | | V | Y | Interface-Id | | | | | | Framed-IPv6- 97 6.11.6 OctetString| M | P | | V | Y | Prefix | | | | | | Framed-IPv6- 99 6.11.7 UTF8String | M | P | | V | Y | Route | | | | | | Framed-IPv6-Pool 100 6.11.8 OctetString| M | P | | V | Y | Framed-IPX- 23 6.12.1 UTF8String | M | P | | V | Y | Network | | | | | | Framed-Appletalk- 37 6.13.1 Unsigned32 | M | P | | V | Y | Link | | | | | | Framed-Appletalk- 38 6.13.2 Unsigned32 | M | P | | V | Y | Network | | | | | | Framed-Appletalk- 39 6.13.3 OctetString| M | P | | V | Y | Zone | | | | | | ARAP-Features 71 6.14.1 OctetString| M | P | | V | Y | ARAP-Zone-Access 72 6.14.2 Enumerated | M | P | | V | Y | Login-IP-Host 14 6.15.1 OctetString| M | P | | V | Y | Login-IPv6-Host 98 6.15.2 OctetString| M | P | | V | Y | Login-Service 15 6.15.3 Enumerated | M | P | | V | Y | Login-TCP-Port 16 6.16.1 Unsigned32 | M | P | | V | Y | Login-LAT-Service 34 6.17.1 OctetString| M | P | | V | Y | Login-LAT-Node 35 6.17.2 OctetString| M | P | | V | Y | Login-LAT-Group 36 6.17.3 OctetString| M | P | | V | Y | Login-LAT-Port 63 6.17.4 OctetString| M | P | | V | Y | -----------------------------------------|----+-----+----+-----|----| .KE .fi .NH 2 Service-Type AVP .XS \*(SN Service-Type AVP .XE .LP .in 3 The Service-Type AVP (AVP Code 6) is of type Enumerated and contains the type of service the user has requested, or the type of service to be provided. One such AVP MAY be present in an authentication and/or authorization request or response. A NAS is not required to implement all of these service types, and MUST treat unknown or unsupported Service-Types received in a response as a failure, and end the session with a DIAMETER_INVALID_AVP_VALUE Result-Code. .sp When used in a request, the Service-Type AVP SHOULD be considered to be a hint to the server that the NAS has reason to believe the user would prefer the kind of service indicated, but the server is not required to honor the hint. Furthermore, if the service specified by the server is supported, but not compatible with the current mode of access, the NAS MUST fail to start the session. The NAS MUST also generate the appropriate error message(s). .sp The following values have been defined for the Service-Type AVP. The complete list of defined values can be found in [RADIUS] and [RADIUSTypes]. The following list is informational: .sp .nf .KS 1 Login 2 Framed 3 Callback Login 4 Callback Framed 5 Outbound 6 Administrative 7 NAS Prompt 8 Authenticate Only 9 Callback NAS Prompt 10 Call Check 11 Callback Administrative 12 Voice 13 Fax 14 Modem Relay 15 IAPP-Register [IEEE 802.11f] 16 IAPP-AP-Check [IEEE 802.11f] 17 Authorize Only [RFC3576] .KE .fi .sp The following values are further qualified: .sp .in 6 Login 1 .in 9 The user should be connected to a host. The message MAY include additional AVPs defined in sections 6.16 or 6.17. .sp .in 6 Framed 2 .in 9 A Framed Protocol should be started for the User, such as PPP or SLIP. The message MAY include additional AVPs defined in sections 6.10, or 7 for tunneling services. .sp .in 6 Callback Login 3 .in 9 The user should be disconnected and called back, then connected to a host. The message MAY include additional AVPs defined in this section. .sp .in 6 Callback Framed 4 .in 9 The user should be disconnected and called back, then a Framed Protocol should be started for the User, such as PPP or SLIP. The message MAY include additional AVPs defined in sections 6.10, or 7 for tunneling services. .sp .in 0 .NH 2 Callback-Number AVP .XS \*(SN Callback-Number AVP .XE .LP .in 3 The Callback-Number AVP (AVP Code 19) is of type UTF8String, and contains a dialing string to be used for callback. It MAY be used in an authentication and/or authorization request as a hint to the server that a Callback service is desired, but the server is not required to honor the hint in the corresponding response. .sp The codification of the range of allowed usage of this field is outside the scope of this specification. .in 0 .sp .NH 2 Callback-Id AVP .XS \*(SN Callback-Id AVP .XE .LP .in 3 The Callback-Id AVP (AVP Code 20) is of type UTF8String, and contains the name of a place to be called, to be interpreted by the NAS. This AVP MAY be present in an authentication and/or authorization response. .sp This AVP is not roaming-friendly since it assumes that the Callback-Id is configured on the NAS. It is therefore preferable to use the Callback-Number AVP instead. .in 0 .sp .NH 2 Idle-Timeout AVP .XS \*(SN Idle-Timeout AVP .XE .LP .in 3 The Idle-Timeout AVP (AVP Code 28) is of type Unsigned32 and sets the maximum number of consecutive seconds of idle connection allowed to the user before termination of the session or a prompt is issued. It MAY be used in an authentication and/or authorization request (or challenge) as a hint to the server that an idle timeout is desired, but the server is not required to honor the hint in the corresponding response. The default is none, or system specific. .in 0 .sp .NH 2 Port-Limit AVP .XS \*(SN Port-Limit AVP .XE .LP .in 3 The Port-Limit AVP (AVP Code 62) is of type Unsigned32 and sets the maximum number of ports to be provided to the user by the NAS. It MAY be used in an authentication and/or authorization request as a hint to the server that multilink PPP [PPPMP] service is desired, but the server is not required to honor the hint in the corresponding response. .sp .NH 2 NAS-Filter-Rule AVP .XS \*(SN NAS-Filter-Rule AVP .XE .LP .in 3 The NAS-Filter-Rule AVP (AVP Code 400) is of type IPFilterRule, and provides filter rules that need to be configured on the NAS for the user. One or more such AVPs MAY be present in an authorization response. .in 0 .sp .NH 2 Filter-Id AVP .XS \*(SN Filter-Id AVP .XE .LP .in 3 The Filter-Id AVP (AVP Code 11) is of type UTF8String, and contains the name of the filter list for this user. Zero or more Filter-Id AVPs MAY be sent in an authorization answer. .sp Identifying a filter list by name allows the filter to be used on different NASes without regard to filter-list implementation details. However, this AVP is not roaming friendly since filter naming differs from one service provider to another. .sp In non-RADIUS environments, it is RECOMMENDED that the NAS-Filter-Rule AVP be used instead. .in 0 .sp .NH 2 Configuration-Token AVP .XS \*(SN Configuration-Token AVP .XE .LP .in 3 The Configuration-Token AVP (AVP Code 78) is of type OctetString and is sent by a Diameter Server to a Diameter Proxy Agent or Translation Agent in an AA-Answer command to indicate a type of user profile to be used. It should not be sent to a Diameter Client (NAS). .sp The format of the Data field of this AVP is site specific. .sp .in 0 .NH 2 QoS-Filter-Rule AVP .XS \*(SN QoS-Filter-Rule AVP .XE .LP .in 3 The QoS-Filter-Rule AVP (AVP Code 407) is of type QoSFilterRule, and provides QoS filter rules that need to be configured on the NAS for the user. One or more such AVPs MAY be present in an authorization response. .sp Note: Due to an editorial mistake in [Base], only the AVP format is discussed. The complete QoSFilterRule definition was not included. It is reprinted here for clarification. .sp QoSFilterRule .sp .in +3 The QosFilterRule format is derived from the OctetString AVP Base Format. It uses the ASCII charset. Packets may be marked or metered based on the following information that is associated with it: .sp .in +3 .nf Direction (in or out) Source and destination IP address (possibly masked) Protocol Source and destination port (lists or ranges) DSCP values (no mask or range) .fi .in 6 .sp Rules for the appropriate direction are evaluated in order, with the first matched rule terminating the evaluation. Each packet is evaluated once. If no rule matches, the packet is treated as best effort. An access device that is unable to interpret or apply a QoS rule SHOULD NOT terminate the session. .sp .in 3 QoSFilterRule filters MUST follow the format: .sp .in 6 action dir proto from src to dst [options] .sp .in 16 .nf tag - Mark packet with a specific DSCP [DIFFSERV]. The DSCP option MUST be included. meter - Meter traffic. The metering options MUST be included. .sp .in 3 dir The format is as described under IPFilterRule. .sp proto The format is as described under IPFilterRule. .sp .in 2 src and dst The format is as described under IPFilterRule. .sp .in 12 options: .sp .in 23 .ti -8 DSCP color values as defined in [DIFFSERV]. Exact matching of DSCP values is required (no masks or ranges). .sp .ti -8 metering The metering option provides Assured Forwarding, as defined in [DIFFSERVAF], and MUST be present if the action is set to meter. The rate option is the throughput, in bits per second, which is used by the access device to mark packets. Traffic above the rate is marked with the color_over codepoint, while traffic under the rate is marked with the color_under codepoint. The color_under and color_over options contain the drop preferences, and MUST conform to the recommended codepoint keywords described in [DIFFSERVAF] (e.g. AF13). .sp The metering option also supports the strict limit on traffic required by Expedited Forwarding, as defined in [DIFFSERVEF]. The color_over option may contain the keyword "drop" to prevent forwarding of traffic that exceeds the rate parameter. .sp .in 9 The rule syntax is a modified subset of ipfw(8) from FreeBSD, and the ipfw.c code may provide a useful base for implementations. .sp .in 0 .NH 2 Framed Access Authorization AVPs .XS \*(SN Framed Access Authorization AVPs .XE .LP .in 3 This section contains the authorization AVPs that are necessary to support framed access, such as PPP, SLIP, etc. AVPs defined in this section MAY be present in a message if the Service-Type AVP was set to "Framed" or "Callback Framed". .in 0 .sp .NH 3 Framed-Protocol AVP .XS \*(SN Framed-Protocol AVP .XE .LP .in 3 The Framed-Protocol AVP (AVP Code 7) is of type Enumerated and contains the framing to be used for framed access. This AVP MAY be present in both requests and responses. The supported values are listed in [RADIUSTypes]. The following list is informational: .nf 1 PPP 2 SLIP 3 AppleTalk Remote Access Protocol (ARAP) 4 Gandalf proprietary SingleLink/MultiLink protocol 5 Xylogics proprietary IPX/SLIP 6 X.75 Synchronous .fi .in 0 .sp .NH 3 Framed-Routing AVP .XS \*(SN Framed-Routing AVP .XE .LP .in 3 The Framed-Routing AVP (AVP Code 10) is of type Enumerated and contains the routing method for the user, when the user is a router to a network. This AVP SHOULD only be present in authorization responses. The supported values are listed in [RADIUSTypes]. The following list is informational: .nf 0 None 1 Send routing packets 2 Listen for routing packets 3 Send and Listen .fi .in 0 .sp .NH 3 Framed-MTU AVP .XS \*(SN Framed-MTU AVP .XE .LP .in 3 The Framed-MTU AVP (AVP Code 12) is of type Unsigned32 and contains the Maximum Transmission Unit to be configured for the user, when it is not negotiated by some other means (such as PPP). This AVP SHOULD only be present in authorization responses. The MTU value MUST be in the range of 64 and 65535. .in 0 .sp .NH 3 Framed-Compression AVP .XS \*(SN Framed-Compression AVP .XE .LP .in 3 The Framed-Compression AVP (AVP Code 13) is of type Enumerated and contains the compression protocol to be used for the link. It MAY be used in an authorization request as a hint to the server that a specific compression type is desired, but the server is not required to honor the hint in the corresponding response. .sp More than one compression protocol AVP MAY be sent. It is the responsibility of the NAS to apply the proper compression protocol to appropriate link traffic. .sp The supported values are listed in [RADIUSTypes]. The following list is informational: .nf 0 None 1 VJ TCP/IP header compression 2 IPX header compression 3 Stac-LZS compression .fi .in 0 .sp .NH 2 IP Access Authorization AVPs .XS \*(SN IP Access Authorization AVPs .XE .LP .in 3 The AVPs defined in this section are used when the user requests, or is being granted, access service to IP. .in 0 .sp .NH 3 Framed-IP-Address AVP .XS \*(SN Framed-IP-Address AVP .XE .LP .in 3 The Framed-IP-Address AVP (AVP Code 8) [RADIUS] is of type OctetString and contains an IPv4 address, of the type specified in the attribute value, to be configured for the user. It MAY be used in an authorization request as a hint to the server that a specific address is desired, but the server is not required to honor the hint in the corresponding response. .sp Two values have special significance; 0xFFFFFFFF and 0xFFFFFFFE. The value 0xFFFFFFFF indicates that the NAS should allow the user to select an address (e.g. Negotiated). The value 0xFFFFFFFE indicates that the NAS should select an address for the user (e.g. Assigned from a pool of addresses kept by the NAS). .in 0 .sp .NH 3 Framed-IP-Netmask AVP .XS \*(SN Framed-IP-Netmask AVP .XE .LP .in 3 The Framed-IP-Netmask AVP (AVP Code 9) is of type OctetString and contains the four octets of the IPv4 netmask to be configured for the user when the user is a router to a network. It MAY be used in an authorization request as a hint to the server that a specific netmask is desired, but the server is not required to honor the hint in the corresponding response. This AVP MUST be present in a response if the request included this AVP with a value of 0xFFFFFFFF. .in 0 .sp .NH 3 Framed-Route AVP .XS \*(SN Framed-Route AVP .XE .LP .in 3 The Framed-Route AVP (AVP Code 22) is of type UTF8String, and contains the ASCII routing information to be configured for the user on the NAS. Zero or more such AVPs MAY be present in an authorization response. .sp The string MUST contain a destination prefix in dotted quad form optionally followed by a slash and a decimal length specifier stating how many high order bits of the prefix should be used. That is followed by a space, a gateway address in dotted quad form, a space, and one or more metrics separated by spaces. For example, "192.168.1.0/24 192.168.1.1 1". .sp The length specifier may be omitted in which case it should default to 8 bits for class A prefixes, 16 bits for class B prefixes, and 24 bits for class C prefixes. For example, "192.168.1.0 192.168.1.1 1". .sp Whenever the gateway address is specified as "0.0.0.0" the IP address of the user SHOULD be used as the gateway address. .in 0 .sp .NH 3 Framed-Pool AVP .XS \*(SN Framed-Pool AVP .XE .LP .in 3 The Framed-Pool AVP (AVP Code 88) is of type OctetString and contains the name of an assigned address pool that SHOULD be used to assign an address for the user. If a NAS does not support multiple address pools, the NAS SHOULD ignore this AVP. Address pools are usually used for IP addresses, but can be used for other protocols if the NAS supports pools for those protocols. .sp Although specified as type OctetString for compatibility with RADIUS [RADIUSExt], the encoding of the Data field SHOULD also conform to the rules for the UTF8String Data Format. .in 0 .sp .NH 3 Framed-Interface-Id AVP .XS \*(SN Framed-Interface-Id AVP .XE .LP .in 3 The Framed-Interface-Id AVP (AVP Code 96) is of type Unsigned64 and contains the IPv6 interface identifier to be configured for the user. It MAY be used in authorization requests as a hint to the server that a specific interface id is desired, but the server is not required to honor the hint in the corresponding response. .in 0 .sp .NH 3 Framed-IPv6-Prefix AVP .XS \*(SN Framed-IPv6-Prefix AVP .XE .LP .in 3 The Framed-IPv6-Prefix AVP (AVP Code 97) is of type OctetString and contains the IPv6 prefix to be configured for the user. One or more AVPs MAY be used in authorization requests as a hint to the server that a specific IPv6 prefixes are desired, but the server is not required to honor the hint in the corresponding response. .in 0 .sp .NH 3 Framed-IPv6-Route AVP .XS \*(SN Framed-IPv6-Route AVP .XE .LP .in 3 The Framed-IPv6-Route AVP (AVP Code 99) is of type UTF8String, and contains the ASCII routing information to be configured for the user on the NAS. Zero or more such AVPs MAY be present in an authorization response. .sp The string MUST contain an IPv6 address prefix followed by a slash and a decimal length specifier stating how many high order bits of the prefix should be used. That is followed by a space, a gateway address in hexadecimal notation, a space, and one or more metrics separated by spaces. For example: .in 6 "2000:0:0:106::/64 2000::106:a00:20ff:fe99:a998 1". .sp .in 3 Whenever the gateway address is the IPv6 unspecified address the IP address of the user SHOULD be used as the gateway address, such as: .in 6 "2000:0:0:106::/64 :: 1". .in 0 .sp .NH 3 Framed-IPv6-Pool AVP .XS \*(SN Framed-IPv6-Pool AVP .XE .LP .in 3 The Framed-IPv6-Pool AVP (AVP Code 100) is of type OctetString, and contains the name of an assigned pool that SHOULD be used to assign an IPv6 prefix for the user. If the access device does not support multiple prefix pools, it MUST ignore this AVP. .sp Although specified as type OctetString for compatibility with RADIUS [RADIUSIPv6], the encoding of the Data field SHOULD also conform to the rules for the UTF8String Data Format. .in 0 .sp .NH 2 IPX Access .XS \*(SN IPX Access .XE .LP .in 3 The AVPs defined in this section are used when the user requests, or is being granted, access to an IPX network service. .in 0 .sp .NH 3 Framed-IPX-Network AVP .XS \*(SN Framed-IPX-Network AVP .XE .LP .in 3 The Framed-IPX-Network AVP (AVP Code 23) is of type Unsigned32, and contains the IPX Network number to be configured for the user. It MAY be used in an authorization request as a hint to the server that a specific address is desired, but the server is not required to honor the hint in the corresponding response. .sp Two addresses have special significance; 0xFFFFFFFF and 0xFFFFFFFE. The value 0xFFFFFFFF indicates that the NAS should allow the user to select an address (e.g. Negotiated). The value 0xFFFFFFFE indicates that the NAS should select an address for the user (e.g. assigned from a pool of one or more IPX networks kept by the NAS). .in 0 .sp .NH 2 AppleTalk Network Access .XS \*(SN AppleTalk Network Access .XE .LP .in 3 The AVPs defined in this section are used when the user requests, or is being granted, access to an AppleTalk network [AppleTalk]. .in 0 .sp .NH 3 Framed-AppleTalk-Link AVP .XS \*(SN Framed-AppleTalk-Link AVP .XE .LP .in 3 The Framed-AppleTalk-Link AVP (AVP Code 37) is of type Unsigned32 and contains the AppleTalk network number which should be used for the serial link to the user, which is another AppleTalk router. This AVP MUST only be present in an authorization response and is never used when the user is not another router. .sp Despite the size of the field, values range from zero to 65535. The special value of zero indicates that this is an unnumbered serial link. A value of one to 65535 means that the serial line between the NAS and the user should be assigned that value as an AppleTalk network number. .in 0 .sp .NH 3 Framed-AppleTalk-Network AVP .XS \*(SN Framed-AppleTalk-Network AVP .XE .LP .in 3 The Framed-AppleTalk-Network AVP (AVP Code 38) is of type Unsigned32 and contains the AppleTalk Network number which the NAS should probe to allocate an AppleTalk node for the user. This AVP MUST only be present in an authorization response and is never used when the user is not another router. Multiple instances of this AVP indicate that the NAS may probe using any of the network numbers specified. .sp Despite the size of the field, values range from zero to 65535. The special value zero indicates that the NAS should assign a network for the user, using its default cable range. A value between one and 65535 (inclusive) indicates the AppleTalk Network the NAS should probe to find an address for the user. .in 0 .sp .NH 3 Framed-AppleTalk-Zone AVP .XS \*(SN Framed-AppleTalk-Zone AVP .XE .LP .in 3 The Framed-AppleTalk-Zone AVP (AVP Code 39) is of type OctetString and contains the AppleTalk Default Zone to be used for this user. This AVP MUST only be present in an authorization response. Multiple instances of this AVP in the same message are not allowed. .sp The codification of the range of allowed usage of this field is outside the scope of this specification. .in 0 .sp .NH 2 AppleTalk Remote Access .XS \*(SN AppleTalk Remote Access .XE .LP .in 3 The AVPs defined in this section are used when the user requests, or is being granted, access to the AppleTalk network via the AppleTalk Remote Access Protocol [ARAP]. They are only present if the Framed-Protocol AVP (see Section 6.10.1) is set to ARAP. Section 2.2 of RFC 2869 [RADIUSExt] describes the operational use of these attributes. .in 0 .sp .NH 3 ARAP-Features AVP .XS \*(SN ARAP-Features AVP .XE .LP .in 3 The ARAP-Features AVP (AVP Code 71) is of type OctetString, and MAY be present in the AA-Accept message if the Framed-Protocol AVP is set to the value of ARAP. See [RADIUSExt] for more information of the format of this AVP. .in 0 .sp .NH 3 ARAP-Zone-Access AVP .XS \*(SN ARAP-Zone-Access AVP .XE .LP .in 3 The ARAP-Zone-Access AVP (AVP Code 72) is of type Enumerated, and MAY be present in the AA-Accept message if the Framed-Protocol AVP is set to the value of ARAP. .sp The supported values are listed in [RADIUSTypes], and are defined in [RADIUSExt]. .in 0 .sp .NH 2 Non-Framed Access Authorization AVPs .XS \*(SN Non-Framed Access Authorization AVPs .XE .LP .in 3 This section contains the authorization AVPs that are needed to support terminal server functionality. AVPs defined in this section MAY be present in a message if the Service-Type AVP was set to "Login" or "Callback Login". .in 0 .sp .NH 3 Login-IP-Host AVP .XS \*(SN Login-IP-Host AVP .XE .LP .in 3 The Login-IP-Host AVP (AVP Code 14) [RADIUS] is of type OctetString and contains the IPv4 address of a host with which to connect the user when the Login-Service AVP is included. It MAY be used in an AA-Request command as a hint to the Diameter Server that a specific host is desired, but the Diameter Server is not required to honor the hint in the AA-Answer. .sp Two addresses have special significance: All ones and 0. The value of all ones indicates that the NAS SHOULD allow the user to select an address. The value 0 indicates that the NAS SHOULD select a host to connect the user to. .in 0 .sp .NH 3 Login-IPv6-Host AVP .XS \*(SN Login-IPv6-Host AVP .XE .LP .in 3 The Login-IPv6-Host AVP (AVP Code 98) [RADIUSIPv6] is of type OctetString and contains the IPv6 address of a host with which to connect the user when the Login-Service AVP is included. It MAY be used in an AA-Request command as a hint to the Diameter Server that a specific host is desired, but the Diameter Server is not required to honor the hint in the AA-Answer. .sp Two addresses have special significance: 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF and 0. The value 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF indicates that the NAS SHOULD allow the user to select an address. The value 0 indicates that the NAS SHOULD select a host to connect the user to. .in 0 .sp .NH 3 Login-Service AVP .XS \*(SN Login-Service AVP .XE .LP .in 3 The Login-Service AVP (AVP Code 15) is of type Enumerated and contains the service which should be used to connect the user to the login host. This AVP SHOULD only be present in authorization responses. .sp The supported values are listed in [RADIUSTypes]. The following list is informational: .nf 0 Telnet 1 Rlogin 2 TCP Clear 3 PortMaster (proprietary) 4 LAT 5 X25-PAD 6 X25-T3POS 8 TCP Clear Quiet (suppresses any NAS-generated connect string) .fi .in 0 .sp .NH 2 TCP Services .XS \*(SN TCP Services .XE .LP .in 3 The AVPs described in this section MAY be present if the Login-Service AVP is set to Telnet, Rlogin, TCP Clear or TCP Clear Quiet. .in 0 .sp .NH 3 Login-TCP-Port AVP .XS \*(SN Login-TCP-Port AVP .XE .LP .in 3 The Login-TCP-Port AVP (AVP Code 16) is of type Unsigned32 and contains the TCP port with which the user is to be connected, when the Login-Service AVP is also present. This AVP SHOULD only be present in authorization responses. The value MUST NOT be greater than 65535. .in 0 .sp .NH 2 LAT Services .XS \*(SN LAT Services .XE .LP .in 3 The AVPs described in this section MAY be present if the Login-Service AVP is set to LAT [LAT]. .in 0 .sp .NH 3 Login-LAT-Service AVP .XS \*(SN Login-LAT-Service AVP .XE .LP .in 3 The Login-LAT-Service AVP (AVP Code 34) is of type OctetString and contains the system with which the user is to be connected by LAT. It MAY be used in an authorization request as a hint to the server that a specific service is desired, but the server is not required to honor the hint in the corresponding response. This AVP MUST only be present in the response if the Login-Service AVP states that LAT is desired. .sp Administrators use the service attribute when dealing with clustered systems, such as a VAX or Alpha cluster. In such an environment several different time sharing hosts share the same resources (disks, printers, etc.), and administrators often configure each to offer access (service) to each of the shared resources. In this case, each host in the cluster advertises its services through LAT broadcasts. .sp Sophisticated users often know which service providers (machines) are faster and tend to use a node name when initiating a LAT connection. Alternately, some administrators want particular users to use certain machines as a primitive form of load balancing (although LAT knows how to do load balancing itself). .sp The String field contains the identity of the LAT service to use. The LAT Architecture allows this string to contain $ (dollar), - (hyphen), . (period), _ (underscore), numerics, upper and lower case alphabetics, and the ISO Latin-1 character set extension [ISOLatin]. All LAT string comparisons are case insensitive. .in 0 .sp .NH 3 Login-LAT-Node AVP .XS \*(SN Login-LAT-Node AVP .XE .LP .in 3 The Login-LAT-Node AVP (AVP Code 35) is of type OctetString and contains the Node with which the user is to be automatically connected by LAT. It MAY be used in an authorization request as a hint to the server that a specific LAT node is desired, but the server is not required to honor the hint in the corresponding response. This AVP MUST only be present in a response if the Login-Service-Type AVP is set to LAT. .sp The String field contains the identity of the LAT service to use. The LAT Architecture allows this string to contain $ (dollar), - (hyphen), . (period), _ (underscore), numerics, upper and lower case alphabetics, and the ISO Latin-1 character set extension [ISOLatin]. All LAT string comparisons are case insensitive. .in 0 .sp .NH 3 Login-LAT-Group AVP .XS \*(SN Login-LAT-Group AVP .XE .LP .in 3 The Login-LAT-Group AVP (AVP Code 36) is of type OctetString and contains a string identifying the LAT group codes which this user is authorized to use. It MAY be used in an authorization request as a hint to the server that a specific group is desired, but the server is not required to honor the hint in the corresponding response. This AVP MUST only be present in a response if the Login-Service-Type AVP is set to LAT. .sp LAT supports 256 different group codes, which LAT uses as a form of access rights. LAT encodes the group codes as a 256 bit bitmap. .sp Administrators can assign one or more of the group code bits at the LAT service provider; it will only accept LAT connections that have these group codes set in the bit map. The administrators assign a bitmap of authorized group codes to each user; LAT gets these from the operating system, and uses these in its requests to the service providers. .sp The codification of the range of allowed usage of this field is outside the scope of this specification. .in 0 .sp .NH 3 Login-LAT-Port AVP .XS \*(SN Login-LAT-Port AVP .XE .LP .in 3 The Login-LAT-Port AVP (AVP Code 63) is of type OctetString and contains the Port with which the user is to be connected by LAT. It MAY be used in an authorization request as a hint to the server that a specific port is desired, but the server is not required to honor the hint in the corresponding response. This AVP MUST only be present in a response if the Login-Service-Type AVP is set to LAT. .sp The String field contains the identity of the LAT service to use. The LAT Architecture allows this string to contain $ (dollar), - (hyphen), . (period), _ (underscore), numerics, upper and lower case alphabetics, and the ISO Latin-1 character set extension [ISOLatin]. All LAT string comparisons are case insensitive. .sp .in 0 .NH 1 NAS Tunneling .XS \*(SN NAS Tunneling .XE .LP .in 3 Some NASes support compulsory tunnel services where the incoming connection data is conveyed by an encapsulation method to a gateway elsewhere in the network. This is typically transparent to the service user, and the tunnel characteristics may be described by the remote AAA server, based on the user's authorization information. Several tunnel characteristics may be returned, and the NAS implementation may choose one. [RADTunnels],[RADTunlAcct] .sp .in 0 .nf .KS +---------------------+ | AVP Flag rules | |----+-----+----+-----|----+ AVP Section | | |SHLD| MUST| | Attribute Name Code Defined Value Type |MUST| MAY | NOT| NOT |Encr| -----------------------------------------|----+-----+----+-----|----| Tunneling 401 7.1 Grouped | M | P | | V | N | Tunnel-Type 64 7.2 Enumerated | M | P | | V | Y | Tunnel-Medium- 65 7.3 Enumerated | M | P | | V | Y | Type | | | | | | Tunnel-Client- 66 7.4 UTF8String | M | P | | V | Y | Endpoint | | | | | | Tunnel-Server- 67 7.5 UTF8String | M | P | | V | Y | Endpoint | | | | | | Tunnel-Password 69 7.6 OctetString| M | P | | V | Y | Tunnel-Private- 81 7.7 OctetString| M | P | | V | Y | Group-Id | | | | | | Tunnel- 82 7.8 OctetString| M | P | | V | Y | Assignment-Id | | | | | | Tunnel-Preference 83 7.9 Unsigned32 | M | P | | V | Y | Tunnel-Client- 90 7.10 UTF8String | M | P | | V | Y | Auth-Id | | | | | | Tunnel-Server- 91 7.11 UTF8String | M | P | | V | Y | Auth-Id | | | | | | -----------------------------------------|----+-----+----+-----|----| .KE .fi .sp .in 0 .NH 2 Tunneling AVP .XS \*(SN Tunneling AVP .XE .LP .in 3 The Tunneling AVP (AVP Code 401) is of type Grouped and contains the following AVPs used to describe a compulsory tunnel service [RADTunnels],[RADTunlAcct]. Its data field has the following ABNF grammar: .sp .nf .in 6 Tunneling ::= < AVP Header: 401 > { Tunnel-Type } { Tunnel-Medium-Type } { Tunnel-Client-Endpoint } { Tunnel-Server-Endpoint } [ Tunnel-Preference ] [ Tunnel-Client-Auth-Id ] [ Tunnel-Server-Auth-Id ] [ Tunnel-Assignment-Id ] [ Tunnel-Password ] [ Tunnel-Private-Group-Id ] .fi .sp .NH 2 Tunnel-Type AVP .XS \*(SN Tunnel-Type AVP .XE .LP .in 3 The Tunnel-Type AVP (AVP Code 64) is of type Enumerated and contains the tunneling protocol(s) to be used (in the case of a tunnel initiator) or the tunneling protocol in use (in the case of a tunnel terminator). It MAY be used in an authorization request as a hint to the server that a specific tunnel type is desired, but the server is not required to honor the hint in the corresponding response. .sp The Tunnel-Type AVP SHOULD also be included in Accounting-Request messages. .sp A tunnel initiator is not required to implement any of these tunnel types; if a tunnel initiator receives a response that contains only unknown or unsupported Tunnel-Types, the tunnel initiator MUST behave as though a response was received with the Result-Code indicating a failure. .sp The supported values are listed in [RADIUSTypes]. The following list is informational: .nf 1 Point-to-Point Tunneling Protocol (PPTP) 2 Layer Two Forwarding (L2F) 3 Layer Two Tunneling Protocol (L2TP) 4 Ascend Tunnel Management Protocol (ATMP) 5 Virtual Tunneling Protocol (VTP) 6 IP Authentication Header in the Tunnel-mode (AH) 7 IP-in-IP Encapsulation (IP-IP) 8 Minimal IP-in-IP Encapsulation (MIN-IP-IP) 9 IP Encapsulating Security Payload in the Tunnel-mode (ESP) 10 Generic Route Encapsulation (GRE) 11 Bay Dial Virtual Services (DVS) 12 IP-in-IP Tunneling 13 Virtual LANs (VLAN) .fi .in 0 .sp .NH 2 Tunnel-Medium-Type AVP .XS \*(SN Tunnel-Medium-Type AVP .XE .LP .in 3 The Tunnel-Medium-Type AVP (AVP Code 65) is of type Enumerated and contains the transport medium to use when creating a tunnel for those protocols (such as L2TP) that can operate over multiple transports. It MAY be used in an authorization request as a hint to the server that a specific medium is desired, but the server is not required to honor the hint in the corresponding response. .sp The supported values are listed in [RADIUSTypes]. The following list is informational: .nf 1 IPv4 (IP version 4) 2 IPv6 (IP version 6) 3 NSAP 4 HDLC (8-bit multidrop) 5 BBN 1822 6 802 (includes all 802 media plus Ethernet "canonical format") 7 E.163 (POTS) 8 E.164 (SMDS, Frame Relay, ATM) 9 F.69 (Telex) 10 X.121 (X.25, Frame Relay) 11 IPX 12 Appletalk 13 Decnet IV 14 Banyan Vines 15 E.164 with NSAP format subaddress .fi .in 0 .sp .NH 2 Tunnel-Client-Endpoint AVP .XS \*(SN Tunnel-Client-Endpoint AVP .XE .LP .in 3 The Tunnel-Client-Endpoint AVP (AVP Code 66) is of type UTF8String, and contains the address of the initiator end of the tunnel. It MAY be used in an authorization request as a hint to the server that a specific endpoint is desired, but the server is not required to honor the hint in the corresponding response. .sp This AVP SHOULD be included in the corresponding Accounting-Request messages, in which case it indicates the address from which the tunnel was initiated. This AVP, along with the Tunnel-Server-Endpoint and Session-Id AVP [Base], MAY be used to provide a globally unique means to identify a tunnel for accounting and auditing purposes. .sp If Tunnel-Medium-Type is IPv4 (1), then this string is either the fully qualified domain name (FQDN) of the tunnel client machine, or it is a "dotted-decimal" IP address. Implementations MUST support the dotted-decimal format and SHOULD support the FQDN format for IP addresses. .sp If Tunnel-Medium-Type is IPv6 (2), then this string is either the FQDN of the tunnel client machine, or it is a text representation of the address in either the preferred or alternate form [IPv6Addr]. Conformant implementations MUST support the preferred form and SHOULD support both the alternate text form and the FQDN format for IPv6 addresses. .sp If Tunnel-Medium-Type is neither IPv4 nor IPv6, this string is a tag referring to configuration data local to the Diameter client that describes the interface or medium-specific client address to use. .in 0 .sp .NH 2 Tunnel-Server-Endpoint AVP .XS \*(SN Tunnel-Server-Endpoint AVP .XE .LP .in 3 The Tunnel-Server-Endpoint AVP (AVP Code 67) is of type UTF8String, and contains the address of the server end of the tunnel. It MAY be used in an authorization request as a hint to the server that a specific endpoint is desired, but the server is not required to honor the hint in the corresponding response. .sp This AVP SHOULD be included in the corresponding Accounting-Request messages, in which case it indicates the address from which the tunnel was initiated. This AVP, along with the Tunnel-Client-Endpoint and Session-Id AVP [Base], MAY be used to provide a globally unique means to identify a tunnel for accounting and auditing purposes. .sp If Tunnel-Medium-Type is IPv4 (1), then this string is either the fully qualified domain name (FQDN) of the tunnel server machine, or it is a "dotted-decimal" IP address. Implementations MUST support the dotted-decimal format and SHOULD support the FQDN format for IP addresses. .sp If Tunnel-Medium-Type is IPv6 (2), then this string is either the FQDN of the tunnel server machine, or it is a text representation of the address in either the preferred or alternate form [IPv6Addr]. Implementations MUST support the preferred form and SHOULD support both the alternate text form and the FQDN format for IPv6 addresses. .sp If Tunnel-Medium-Type is not IPv4 or IPv6, this string is a tag referring to configuration data local to the Diameter client that describes the interface or medium-specific server address to use. .in 0 .sp .NH 2 Tunnel-Password AVP .XS \*(SN Tunnel-Password AVP .XE .LP .in 3 The Tunnel-Password AVP (AVP Code 69) is of type OctetString and may contain a password to be used to authenticate to a remote server. The Tunnel-Password AVP contains sensitive information. This value is not protected in the same manner as RADIUS [RADTunnels]. .sp As required in [Base], Diameter messages are encrypted using IPsec or TLS. The Tunnel-Password AVP SHOULD NOT be used in untrusted proxy environments without encrypting it using end-to-end security techniques, such as CMS Security [DiamCMS]. .in 0 .sp .NH 2 Tunnel-Private-Group-Id AVP .XS \*(SN Tunnel-Private-Group-Id AVP .XE .LP .in 3 The Tunnel-Private-Group-Id AVP (AVP Code 81) is of type OctetString, and contains the group Id for a particular tunneled session. The Tunnel-Private-Group-Id AVP MAY be included in an authorization request if the tunnel initiator can pre-determine the group resulting from a particular connection and SHOULD be included in the authorization response if this tunnel session is to be treated as belonging to a particular private group. Private groups may be used to associate a tunneled session with a particular group of users. For example, it MAY be used to facilitate routing of unregistered IP addresses through a particular interface. This AVP SHOULD be included in the Accounting-Request messages which pertain to the tunneled session. .in 0 .sp .NH 2 Tunnel-Assignment-Id AVP .XS \*(SN Tunnel-Assignment-Id AVP .XE .LP .in 3 The Tunnel-Assignment-Id AVP (AVP Code 82) is of type OctetString and is used to indicate to the tunnel initiator the particular tunnel to which a session is to be assigned. Some tunneling protocols, such as [PPTP] and [L2TP], allow for sessions between the same two tunnel endpoints to be multiplexed over the same tunnel and also for a given session to utilize its own dedicated tunnel. This attribute provides a mechanism for Diameter to be used to inform the tunnel initiator (e.g. PAC, LAC) whether to assign the session to a multiplexed tunnel or to a separate tunnel. Furthermore, it allows for sessions sharing multiplexed tunnels to be assigned to different multiplexed tunnels. .sp A particular tunneling implementation may assign differing characteristics to particular tunnels. For example, different tunnels may be assigned different QoS parameters. Such tunnels may be used to carry either individual or multiple sessions. The Tunnel-Assignment-Id attribute thus allows the Diameter server to indicate that a particular session is to be assigned to a tunnel that provides an appropriate level of service. It is expected that any QoS-related Diameter tunneling attributes defined in the future that accompany this attribute will be associated by the tunnel initiator with the Id given by this attribute. In the meantime, any semantic given to a particular Id string is a matter left to local configuration in the tunnel initiator. .sp The Tunnel-Assignment-Id AVP is of significance only to Diameter and the tunnel initiator. The Id it specifies is intended to be of only local use to Diameter and the tunnel initiator. The Id assigned by the tunnel initiator is not conveyed to the tunnel peer. .sp This attribute MAY be included in authorization responses. The tunnel initiator receiving this attribute MAY choose to ignore it and assign the session to an arbitrary multiplexed or non-multiplexed tunnel between the desired endpoints. This AVP SHOULD also be included in the Accounting-Request messages which pertain to the tunneled session. .sp If a tunnel initiator supports the Tunnel-Assignment-Id AVP, then it should assign a session to a tunnel in the following manner: .sp .in 8 .ti -2 - If this AVP is present and a tunnel exists between the specified endpoints with the specified Id, then the session should be assigned to that tunnel. .sp .ti -2 - If this AVP is present and no tunnel exists between the specified endpoints with the specified Id, then a new tunnel should be established for the session and the specified Id should be associated with the new tunnel. .sp .ti -2 - If this AVP is not present, then the session is assigned to an unnamed tunnel. If an unnamed tunnel does not yet exist between the specified endpoints then it is established and used for this and subsequent sessions established without the Tunnel-Assignment-Id attribute. A tunnel initiator MUST NOT assign a session for which a Tunnel-Assignment-Id AVP was not specified to a named tunnel (i.e. one that was initiated by a session specifying this AVP). .sp .in 3 Note that the same Id may be used to name different tunnels if such tunnels are between different endpoints. .in 0 .NH 2 Tunnel-Preference AVP .XS \*(SN Tunnel-Preference AVP .XE .LP .in 3 The Tunnel-Preference AVP (AVP Code 83) is of type Unsigned32 and is used to identify the relative preference assigned to each tunnel when more than one set of tunneling AVPs is returned within separate Grouped-AVP AVPs. It MAY be used in an authorization request as a hint to the server that a specific preference is desired, but the server is not required to honor the hint in the corresponding response. .sp For example, suppose that AVPs describing two tunnels are returned by the server, one with a Tunnel-Type of PPTP and the other with a Tunnel-Type of L2TP. If the tunnel initiator supports only one of the Tunnel-Types returned, it will initiate a tunnel of that type. If, however, it supports both tunnel protocols, it SHOULD use the value of the Tunnel-Preference AVP to decide which tunnel should be started. The tunnel having the numerically lowest value in the Value field of this AVP SHOULD be given the highest preference. The values assigned to two or more instances of the Tunnel-Preference AVP within a given authorization response MAY be identical. In this case, the tunnel initiator SHOULD use locally configured metrics to decide which set of AVPs to use. .in 0 .sp .NH 2 Tunnel-Client-Auth-Id AVP .XS \*(SN Tunnel-Client-Auth-Id AVP .XE .LP .in 3 The Tunnel-Client-Auth-Id AVP (AVP Code 90) is of type UTF8String and specifies the name used by the tunnel initiator during the authentication phase of tunnel establishment. It MAY be used in an authorization request as a hint to the server that a specific preference is desired, but the server is not required to honor the hint in the corresponding response. This AVP MUST be present in the authorization response if an authentication name other than the default is desired. This AVP SHOULD be included in the Accounting-Request messages which pertain to the tunneled session. .in 0 .sp .NH 2 Tunnel-Server-Auth-Id AVP .XS \*(SN Tunnel-Server-Auth-Id AVP .XE .LP .in 3 The Tunnel-Server-Auth-Id AVP (AVP Code 91) is of type UTF8String and specifies the name used by the tunnel terminator during the authentication phase of tunnel establishment. It MAY be used in an authorization request as a hint to the server that a specific preference is desired, but the server is not required to honor the hint in the corresponding response. This AVP MUST be present in the authorization response if an authentication name other than the default is desired. This AVP SHOULD be included in the the Accounting-Request messages which pertain to the tunneled session. .sp .in 0 .NH 1 NAS Accounting .XS \*(SN NAS Accounting .XE .LP .in 3 Applications implementing this specification use Diameter Accounting as defined in the Base [Base] with the addition of the AVPs in the following section. Service specific AVP usage is defined in the tables in Section 10. .sp If accounting is active, Accounting Request messages (ACR) SHOULD be sent after the completion of any Authentication or Authorization transaction and at the end of a Session. The Accounting-Record-Type value indicates the type of event. All other AVPs identify the session and provide additional information relevant to the event. .sp The successful completion of the first Authentication or Authorization transaction, SHOULD cause a START_RECORD to be sent. If additional Authentications or Authorizations occur in later transactions, the first exchange should generate a START_RECORD, and the later, an INTERIM_RECORD. For a given session, there MUST only be one set of matching START and STOP records, with any number of INTERIM_RECORDS in between, or one EVENT_RECORD indicating the reason for not starting a session. .sp The following table describes the AVPs, their AVP Code values, types, possible flag values and whether the AVP MAY be encrypted. .sp .nf .in 3 .KS +---------------------+ | AVP Flag rules | |----+-----+----+-----|----+ AVP Section | | |SHLD| MUST| | Attribute Name Code Defined Value Type |MUST| MAY | NOT| NOT|Encr| -----------------------------------------|----+-----+----+-----|----| Accounting- 363 8.1 Unsigned64 | M | P | | V | Y | Input-Octets | | | | | | Accounting- 364 8.2 Unsigned64 | M | P | | V | Y | Output-Octets | | | | | | Accounting- 365 8.3 Unsigned64 | M | P | | V | Y | Input-Packets | | | | | | Accounting- 366 8.4 Unsigned64 | M | P | | V | Y | Output-Packets | | | | | | Acct-Session-Time 46 8.5 Unsigned32 | M | P | | V | Y | Acct-Authentic 45 8.6 Enumerated | M | P | | V | Y | Acounting-Auth- 406 8.7 Enumerated | M | P | | V | Y | Method | | | | | | Acct-Delay-Time 41 8.8 Unsigned32 | M | P | | V | Y | Acct-Link-Count 51 8.9 Unsigned32 | M | P | | V | Y | Acct-Tunnel- 68 8.10 OctetString| M | P | | V | Y | Connection | | | | | | Acct-Tunnel- 86 8.11 Unsigned32 | M | P | | V | Y | Packets-Lost | | | | | | -----------------------------------------|----+-----+----+-----|----| .KE .fi .in 0 .sp .NH 2 Accounting-Input-Octets AVP .XS \*(SN Accounting-Input-Octets AVP .XE .LP .in 3 The Accounting-Input-Octets AVP (AVP Code 363) is of type Unsigned64, and contains the number of octets received from the user. .sp For NAS usage, this AVP indicates how many octets have been received from the port in the course of this session and can only be present in ACR messages with an Accounting-Record-Type of INTERIM_RECORD or STOP_RECORD. .in 0 .sp .NH 2 Accounting-Output-Octets AVP .XS \*(SN Accounting-Output-Octets AVP .XE .LP .in 3 The Accounting-Output-Octets AVP (AVP Code 364) is of type Unsigned64, and contains the number of octets sent to the user. .sp For NAS usage, this AVP indicates how many octets have been sent to the port in the course of this session and can only be present in ACR messages with an Accounting-Record-Type of INTERIM_RECORD or STOP_RECORD. .in 0 .sp .sp .NH 2 Accounting-Input-Packets AVP .XS \*(SN Accounting-Input-Packets AVP .XE .LP .in 3 The Accounting-Input-Packets (AVP Code 365) is of type Unsigned64, and contains the number of packets received from the user. .sp For NAS usage, this AVP indicates how many packets have been received from the port over the course of a session being provided to a Framed User and can only be present in ACR messages with an Accounting-Record-Type of INTERIM_RECORD or STOP_RECORD. .in 0 .sp .NH 2 Accounting-Output-Packets AVP .XS \*(SN Accounting-Output-Packets AVP .XE .LP .in 3 The Accounting-Output-Packets (AVP Code 366) is of type Unsigned64, and contains the number of IP packets sent to the user. .sp For NAS usage, this AVP indicates how many packets have been sent to the port over the course of a session being provided to a Framed User and can only be present in ACR messages with an Accounting-Record-Type of INTERIM_RECORD or STOP_RECORD. .in 0 .sp .NH 2 Acct-Session-Time AVP .XS \*(SN Acct-Session-Time AVP .XE .LP .in 3 The Acct-Session-Time AVP (AVP Code 46) is of type Unsigned32, and indicates the length of the current session in seconds. It can only be present in ACR messages with an Accounting-Record-Type of INTERIM_RECORD or STOP_RECORD. .in 0 .NH 2 Acct-Authentic AVP .XS \*(SN Acct-Authentic AVP .XE .LP .in 3 The Acct-Authentic AVP (AVP Code 45) is of type Enumerated, and specifies how the user was authenticated. The supported values are listed in [RADIUSTypes]. The following list is informational: .nf 1 RADIUS 2 Local 3 Remote 4 Diameter .in 0 .sp .NH 2 Accounting-Auth-Method AVP .XS \*(SN Accounting-Auth-Method AVP .XE .LP .in 3 The Accounting-Auth-Method AVP (AVP Code 406) is of type Enumerated. A NAS MAY include this AVP in an Accounting-Request message to indicate what authentication method was used to authenticate the user. (Note that this is equivalent to the RADIUS MS-Acct-Auth-Type VSA attribute). .sp The following values are defined: .nf 1 PAP 2 CHAP 3 MS-CHAP-1 4 MS-CHAP-2 5 EAP 7 None .in 0 .sp .NH 2 Acct-Delay-Time .XS \*(SN Acct-Delay-Time .XE .LP .in 3 The Acct-Delay-Time AVP (AVP Code 41) is of type Unsigned32 and indicates the number of seconds during which the Diameter client has been trying to send the Accounting-Request (ACR) which contains it. The accounting server may subtract this value from the time the ACR arrives at the server to calculate the approximate time of the event that caused the ACR to be generated. .sp This AVP is not used for retransmissions at the transport level (TCP or SCTP). Rather, it may be used when an ACR command cannot be transmitted because there is no appropriate peer to transmit it to or was rejected because it could not be delivered to its destination. In these cases, the command MAY be buffered and transmitted some time later when an appropriate peer-connection is available or after sufficient time has passed that the destination-host may be reachable and operational. If the ACR is resent in this way the Acct-Delay-Time AVP SHOULD be included. The value of this AVP indicates the number of seconds that elapsed between the time of the first attempt at transmission and the current attempt at transmission. .in 0 .sp .NH 2 Acct-Link-Count .XS \*(SN Acct-Link-Count .XE .LP .in 3 The Acct-Link-Count AVP (AVP Code 51) is of type Unsigned32 and indicates the total number of links that have been active (current or closed) in a given multilink session, at the time the accounting record is generated. This AVP MAY be included in Accounting-Requests for any session which may be part of a multilink service. .sp The Acct-Link-Count AVP may be used to make it easier for an accounting server to know when it has all the records for a given multilink service. When the number of Accounting-Requests received with Accounting-Record-Type = STOP_RECORD and the same Acct-Multi-Session-Id and unique Session-Id's equals the largest value of Acct-Link-Count seen in those Accounting-Requests, all STOP_RECORD Accounting-Requests for that multilink service have been received. .sp The following example showing eight Accounting-Requests illustrates how the Acct-Link-Count AVP is used. In the table below, only the relevant AVPs are shown although additional AVPs containing accounting information will also be present in the Accounting-Requests. .sp .nf Acct-Multi- Accounting- Acct- Session-Id Session-Id Record-Type Link-Count -------------------------------------------------------- "...10" "...10" START_RECORD 1 "...10" "...11" START_RECORD 2 "...10" "...11" STOP_RECORD 2 "...10" "...12" START_RECORD 3 "...10" "...13" START_RECORD 4 "...10" "...12" STOP_RECORD 4 "...10" "...13" STOP_RECORD 4 "...10" "...10" STOP_RECORD 4 .fi .in 0 .sp .NH 2 Acct-Tunnel-Connection AVP .XS \*(SN Acct-Tunnel-Connection AVP .XE .LP .in 3 The Acct-Tunnel-Connection AVP (AVP Code 68) is of type OctetString, and contains the identifier assigned to the tunnel session. This AVP, along with the Tunnel-Client-Endpoint and Tunnel-Server-Endpoint AVPs, may be used to provide a means to uniquely identify a tunnel session for auditing purposes. .sp The format of the identifier in this AVP depends upon the value of the Tunnel-Type AVP. For example, to fully identify an L2TP tunnel connection, the L2TP Tunnel Id and Call Id might be encoded in this field. The exact encoding of this field is implementation dependent. .in 0 .sp .NH 2 Acct-Tunnel-Packets-Lost AVP .XS \*(SN Acct-Tunnel-Packets-Lost AVP .XE .LP .in 3 The Acct-Tunnel-Packets-Lost AVP (AVP Code 86) is of type Unsigned32 and contains the number of packets lost on a given link. .in 0 .sp .NH 1 RADIUS/Diameter Protocol Interactions .XS \*(SN RADIUS/Diameter Protocol Interactions .XE .LP .in 3 This section describes some basic guidelines that may be used by servers that act as AAA Translation Agents. A complete description of all the differences between RADIUS and Diameter is beyond the scope of this section and document. Note that this document does not restrict implementations from creating additional translation methods, as long as the translation function doesn't violate the RADIUS or the Diameter protocols. .sp While the Diameter protocol is in many ways a superset of RADIUS functions, there are a number of RADIUS representations that are not allowed, so as to best use the new capabilities without the older problems. .sp There are primarily two different situations that must be handled; one where a RADIUS request is received that must be forwarded as a Diameter request, and the inverse. RADIUS does not support a peer-to-peer architecture and server initiated operations are generally not supported. See [RADDynAuth] for an alternative. .sp Some RADIUS attributes are encrypted. RADIUS security and encryption techniques are applied on a hop-per-hop basis. A Diameter agent will have to decrypt RADIUS attribute data entering the Diameter system and if that information is forwarded, MUST secure it using Diameter specific techniques. .sp Note that this section uses the two terms; "AVP" and "attribute" in a concise and specific manner. The former is used to signify a Diameter AVP, while the latter is used to signify a RADIUS attribute. .sp .NH 2 RADIUS Request Forwarded as Diameter Request .XS \*(SN RADIUS Request Forwarded as Diameter Request .XE .LP .in 3 This section describes the actions that should be followed when a Translation Agent receives a RADIUS message that is to be translated to a Diameter message. .sp It is important to note that RADIUS servers are assumed to be stateless, and this section maintains that assumption. It is also quite possible for the RADIUS messages that comprise the session (i.e. authentication and accounting messages) will be handled by different Translation Agents in the proxy network. Therefore, a RADIUS/Diameter Translation Agent SHOULD NOT be assumed to have an accurate track on session state information. .sp When a Translation Agent receives a RADIUS message, the following steps should be taken: .sp .in 8 .ti -2 - If a Message-Authenticator attribute is present, the value MUST be checked, but not included in the Diameter message. If it is incorrect, the RADIUS message should be silently discarded. The gateway system SHOULD generate and include a Message-Authenticator in return RADIUS responses to this system. .ti -2 - The transport address of the sender MUST be checked against the NAS identifying attributes. See the description of NAS-Identifier and NAS-IP-Address below. .ti -2 - The Translation Agent must maintain transaction state information relevant to the RADIUS request, such as the Identifier field in the RADIUS header, any existing RADIUS Proxy-State attribute as well as the source IP address and port number of the UDP packet. These may be maintained locally in a state table, or may be saved in a Proxy-Info AVP group. A Diameter Session-Id AVP value must be created using a session state mapping mechanism. .ti -2 - If the RADIUS request contained a State attribute, and the prefix of the data is "Diameter/", the data following the prefix contains the Diameter Origin-Host/Origin-Realm/Session-Id. If no such attributes are present, and the RADIUS command is an Access-Request, a new Session-Id is created. The Session-Id is included in the Session-Id AVP. .ti -2 - The Diameter Origin-Host and Origin-Realm AVPs MUST be created and added using the information from an FQDN corresponding to the NAS-IP-Address attribute (preferred if available), and/or the NAS-Identifier attribute. (Note that the RADIUS NAS-Identifier is not required to be an FQDN) .ti -2 - The Proxy-Info group SHOULD be added with the local server's identity being specified in the Proxy-Host AVP. This should ensure that the response is returned to this system. .ti -2 - The Destination-Realm AVP is created from the information found in the RADIUS User-Name attribute. .ti -2 - If the RADIUS User-Password attribute is present, the password must be unencrypted using the link's RADIUS shared secret. And the unencrypted value forwarded in a User-Password AVP using Diameter security. .ti -2 - If the RADIUS CHAP-Password attribute is present, the Ident and Data portion of the attribute are used to create the CHAP-Auth grouped AVP. .ti -2 - If the RADIUS message contains an address attribute, it MUST be converted to the appropriate Diameter AVP and type. .ti -2 - If the RADIUS message contains Tunnel information [RADTunnels], the attributes or tagged groups should each be converted to a Diameter Tunneling Grouped AVP set. If the tunnel information contains a Tunnel-Password attribute, the RADIUS encryption must be resolved, and the password forwarded using Diameter security methods. .ti -2 - If the RADIUS message received is an Accounting-Request, the Acct-Status-Type attribute value must be converted to a Accounting-Record-Type AVP value. If the Acct-Status-Type attribute value is STOP, the local server MUST issue a Session-Termination-Request message once the Diameter Accounting-Answer message has been received. .ti -2 - If the Accounting message contains a Acct-Termination-Cause attribute, it should be translated to the equivalent Termination-Cause AVP value. (see below) .ti -2 - If the RADIUS message contains the Accounting-Input-Octets, Accounting-Input-Packets, Accounting-Output-Octets or Accounting-Output-Packets, these attributes must be converted to the Diameter equivalent ones. Further, if the Acct-Input-Gigawords or Acct-Output-Gigawords attributes are present, these must be used to properly compute the Diameter accounting AVPs. .sp .in 3 The corresponding Diameter response is always guaranteed to be received by the same Translation Agent that translated the original request, due to the contents of the Proxy-Info AVP group in the Diameter request. The following steps are applied to the response message during the Diameter to RADIUS translation: .sp .in 8 .ti -2 - If the Diameter Command-Code is set to AA-Answer and the Result-Code AVP is set to DIAMETER_MULTI_ROUND_AUTH, the gateway must send a RADIUS Access-Challenge with the Origin-Host, Origin-Realm, and Diameter Session-Id AVPs encapsulated in the RADIUS State attribute, with the prefix "Diameter/", concatented in the above order, in UTF-8, [UTF-8] separated with "/" characters. This is necessary in order to ensure that the Translation Agent that will receive the subsequent RADIUS Access-Request will have access to the Session Identifier, and be able to set the Destination-Host to the correct value. If the Multi-Round-Time-Out AVP is present, the value of the AVP MUST be inserted in the RADIUS Session-Timeout AVP. .ti -2 - If the Command-Code is set to AA-Answer, the Diameter Session-Id AVP is saved in a new RADIUS Class attribute, whose format consists of the string "Diameter/" followed by the Diameter Session Identifier. This will ensure that the subsequent Accounting messages, which could be received by any Translation Agent, would have access to the original Diameter Session Identifier. .ti -2 - If a Proxy-State attribute was present in the RADIUS request, the same attribute is added in the response. This information may be found in the Proxy-Info AVP group, or in a local state table. .ti -2 - If state information regarding the RADIUS request was saved in a Proxy-Info AVPs or local state table, the RADIUS Identifier and UDP IP Address and port number are extracted and used in issuing the RADIUS reply. .sp .in 3 When translating a Diameter AA-Answer (with successful result code) to RADIUS Access-Accept, that contains a Session-Timeout or Authorization-Lifetime AVP; .sp .in 8 .ti -2 - If the Diameter message contains a Session-Timeout AVP but no Authorization-Lifetime AVP, translate it to Session-Timeout attribute (and no Termination-Action). .ti -2 - If the Diameter message contains a Authorization-Lifetime AVP but no Session-Timeout AVP, translate it to Session-Timeout attribute and Termination-Action set to AA-REQUEST. (And remove Authorization-Lifetime and Re-Auth-Request-Type) .ti -2 - If the Diameter message has both, the Session-Timeout must be greater or equal than Authorization-Lifetime (required by Base). Translate it to a Session-Timeout value (with value from Authorization-Lifetime AVP, the smaller one) and Termination-Action set to AA-REQUEST. (And remove Authorization-Lifetime and Re-Auth-Request-Type) .sp .in 0 .NH 3 RADIUS Dynamic Authorization considerations .XS \*(SN RADIUS Dynamic Authorization considerations .XE .LP .in 3 A Diameter/RADIUS gateway may be communicating with a server that implements RADIUS Dynamic Authorization [RADDynAuth]. If it supports these functions it MUST be listening on the assigned port, and would receive RADIUS CoA-Request and Disconnect-Request messages. These can be mapped into the Diameter Re-Auth-Request (RAR) and Abort-Session-Request (ASR) message exchanges respectively [Base]. .sp If the [RADDynAuth] is not supported, the port would not be active and the RADIUS server would receive a ICMP Port Unreachable indication. Alternatively, if the messages are received, but with an inappropriate Service-Type, the gateway can respond with the appropriate NAK message and an Error-Cause attribute with the value of 405, "Unsupported Service". .sp The RADIUS CoA-Request and Disconnect-Request messages will not contain a Diameter Session-Id. Diameter requires this value to match an active session context. The gateway MUST have a session id cache (or other means) to be able to identify the sessions that these functions pertain to. If unable to identify the session, the gateway (or NAS) should return an Error-Cause value 503, "Session Context Not Found". .sp The RADIUS CoA-Request message only supports a change of authorization attributes, and the received CoA-Request SHOULD include a Service-Type of "Authorize-Only", this indicates an extended exchange request by the rules given in [RADDynAuth] Section 3.2 Note 6. This is the only type of exchange supported by Diameter [Base]. .sp For the CoA-Request, the translated RAR message will have a Re-Auth-Type of AUTHORIZE_ONLY. The returned RAA will be translated into a CoA-NAK with Error-Cause "Request Initiated", the gateway's Diameter client SHOULD also start a reauthorization sequence by sending a AAR message, which will be translated into an Access-Request message. The RADIUS server will use the Access-Accept (or Access-Reject) message to convey the new authorization attributes, which the gateway will pass back in an AAA message. .sp Any attributes included in the COA-Request or Access-Accept message are to be considered mandatory in Diameter, and if they cannot be supported, MUST result in an message error return to the RADIUS server with an Error-Cause of "Unsupported Attribute". The Diameter NAS will attempt to apply all the attributes supplied in the AA message to the session. .sp A RADIUS Disconnect-Request message received by the gateway would be translated to a Diameter Abort-Session-Request (ASR) message [Base]. The results will be returned by the Diameter client in a Abort-Session-Answer (ASA) message. A success indication would translate to a RADIUS Disconnect-ACK, a failure would generate a Disconnect-NAK. .sp .in 0 .NH 2 Diameter Request Forwarded as RADIUS Request .XS \*(SN Diameter Request Forwarded as RADIUS Request .XE .LP .in 3 When a server receives a Diameter request that is to be forwarded to a RADIUS entity, the following steps are an example of the steps that may be followed: .sp .in 8 .ti -2 - The Origin-Host AVP's value is inserted in the NAS-Identifier attribute. .ti -2 - The following information MUST be present in the corresponding Diameter response, and therefore MUST be saved either in a local state table, or encoded in a RADIUS Proxy-State attribute: .in 14 .ti -3 1. Origin-Host AVP .ti -3 2. Session-Id AVP .ti -3 3. Proxy-Info AVP .ti -3 4. Any other AVP that MUST be present in the response, and has no corresponding RADIUS attribute. .in 8 .ti -2 - If the CHAP-Auth AVP is present, the grouped AVPs are used to create the RADIUS CHAP-Password attribute data. .ti -2 - If the User-Password AVP is present, the data should be encrypted and forwarded using RADIUS rules. Likewise for any other RADIUS encrypted attribute values. .ti -2 - AVPs that are of the type Address, must be translated to the corresponding RADIUS attribute. .ti -2 - If the Accounting-Input-Octets, Accounting-Input-Packets, Accounting-Output-Octets or Accounting-Output-Packets AVPs are present, these must be translated to the corresponding RADIUS attributes. Further, the value of the Diameter AVPs do not fit within a 32-bit RADIUS attribute, the RADIUS Acct-Input-Gigawords and Acct-Output-Gigawords must be used. .ti -2 - If the RADIUS link supports the Message-Authenticator attribute [RADIUSExt] it SHOULD be generated and added to the request. .sp .in 3 When the corresponding response is received by the Translation Agent, which is guaranteed in the RADIUS protocol, the following steps may be followed: .sp .in 8 .ti -2 - If the RADIUS code is set to Access-Challenge, a Diameter AA-Answer message is created with the Result-Code set to DIAMETER_MULTI_ROUND_AUTH. If the Session-Timeout AVP is present in the RADIUS message, its value is inserted in the Multi-Round-Time-Out AVP. .ti -2 - If a Proxy-State attribute is present, extract the encoded information, otherwise retrieve the original Proxy-Info AVP group information from the local state table. .ti -2 - The response's Origin-Host information is created from the FQDN of the source IP address of the RADIUS message. The same FQDN is also stored to a Route-Record AVP. .ti -2 - The response's Destination-Host AVP is copied from the saved request's Origin-Host information. .ti -2 - The Session-Id information can be recovered from local state, or from the constructed State or Proxy-State attribute as above. .ti -2 - If a Proxy-Info AVP was present in the request, the same AVP MUST be added to the response. .ti -2 - If the RADIUS State attributes are present, these attributes must be present in the Diameter response, minus those added by the gateway. .ti -2 - Any other AVPs that were saved at request time, and MUST be present in the response, are added to the message. .sp .in 3 When translating a RADIUS Access-Accept to Diameter AA-Answer, that contains a Session-Timeout attribute, do the following: .sp .in 8 .ti -2 - If the RADIUS message contains a Session-Timeout attribute and a Termination-Action attribute set to DEFAULT (or no Termination-Action attribute at all), translate it to AA-Answer with a Session-Timeout AVP, and remove the Termination-Action attribute. .ti -2 - If the RADIUS message contains a Session-Timeout attribute and a Termination-Action attribute set to AA-REQUEST, translate it to AA-Answer with Authorization-Lifetime AVP and Re-Auth-Request-Type set to AUTHORIZE_AUTHENTICATE, and remove the Session-Timeout attribute. .sp .in 0 .NH 3 RADIUS Dynamic Authorization considerations .XS \*(SN RADIUS Dynamic Authorization considerations .XE .LP .in 3 A RADIUS/Diameter gateway that is communicating with a RADIUS client that implements RADIUS Dynamic Authorization [RADDynAuth], may translate Diameter Re-Auth-Request (RAR) messages and Abort-Session-Request (ASR) messages [Base] into RADIUS CoA-Request and Disconnect-Request messages respectively. .sp If the RADIUS client does not support the capability, the gateway will receive an ICMP Port Unreachable indication when it transmits the RADIUS message. Even if the NAS supports [RADDynAuth], it may not support the Service-Type in the request message. In this case it will respond with a NAK message and (optionally) an Error-Cause attribute with value 405, "Unsupported Service". If the gateway encounters these error conditions, or if it does not support [RADDynAuth], it sends a Diameter Answer message with an Result-Code AVP of "DIAMETER_COMMAND_UNSUPPORTED" to the AAA server. .sp When encoding the RADIUS messages, the gateway MUST include the Diameter Session-ID in the RADIUS State attribute value, as mentioned above. The RADIUS client should return it in the response. .sp A Diameter Re-Auth-Request (RAR) message [Base] received by the gateway will be translated into a RADIUS CoA-Request and sent to the RADIUS client. The RADIUS client should respond with a CoA-ACK or CoA-NAK message, that the gateway should translate into an Re-Auth-Answer (RAA) message. .sp If the gateway receives a RADIUS CoA-NAK response containing a Service-Type Attribute with value "Authorize Only" and an Error-Cause Attribute with value "Request Initiated", this indicates an extended exchange request by the rules given in [RADDynAuth] Section 3.2 Note 6. .sp The response is translated to a Diameter Re-Auth-Answer (RAA) with a Result-Code AVP of "DIAMETER_LIMITED_SUCCESS" sent to the AAA server. .sp Subsequently, the gateway should receive a RADIUS Access-Request from the NAS, with a Service-Type of "Authorize Only". This is translated to a Diameter AA-Request with an Auth-Request-Type AVP of AUTHORIZE_ONLY, sent to the AAA server. The AAA server will then reply with a Diameter AA-Answer, which is translated to a RADIUS Access-Accept or Access-Reject, depending on the value of the Result-Code AVP. .sp A Diameter Abort-Session-Request (ASR) message [Base] received by the gateway will be translated into a RADIUS Disconnect-Request and sent to the RADIUS client. The RADIUS client should respond with a Disconnect-ACK or Disconnect-NAK message, that the gateway should translate into an Abort-Session-Answer (ASA) message. .sp If the gateway receives a RADIUS Disconnect-NAK response containing a Service-Type Attribute with value "Authorize Only" and an Error-Cause Attribute with value "Request Initiated", the Disconnect-NAK response is translated to a Diameter Abort-Session-Answer (ASA) with a Result-Code AVP of "DIAMETER_LIMITED_SUCCESS" sent to the AAA server. .sp Subsequently, the gateway should receive a RADIUS Access-Request from the NAS, with a Service-Type of "Authorize Only". This is translated to a Diameter AA-Request with an Auth-Request-Type AVP of AUTHORIZE_ONLY, sent to the AAA server. The AAA server will then reply with a Diameter AA-Answer, which is translated to a RADIUS Access-Accept or Access-Reject, depending on the value of the Result-Code AVP. .sp .in 0 .NH 2 AVPs Used Only for Compatibility .XS \*(SN AVPs Used Only for Compatibility .XE .LP .in 3 The AVPs defined in this section SHOULD only used for backwards compatibility when a Diameter/RADIUS translation function is invoked, and are not typically originated by Diameter systems during normal operations. .sp .KS .nf .in 3 +---------------------+ | AVP Flag rules | |----+-----+----+-----|----+ AVP Section | | |SHLD| MUST| | Attribute Name Code Defined Value Type |MUST| MAY | NOT| NOT|Encr| -----------------------------------------|----+-----+----+-----|----| NAS-Identifier 32 9.3.1 UTF8String | M | P | | V | Y | NAS-IP-Address 4 9.3.2 OctetString| M | P | | V | Y | NAS-IPv6-Address 95 9.3.3 OctetString| M | P | | V | Y | State 24 9.3.4 OctetString| M | P | | V | Y | Termination- 295 9.3.5 Enumerated | M | P | | V | Y | Cause | | | | | | -----------------------------------------|----+-----+----+-----|----| .KE .fi .in 0 .sp .NH 3 NAS-Identifier AVP .XS \*(SN NAS-Identifier AVP .XE .LP .in 3 The NAS-Identifier AVP (AVP Code 32) [RADIUS] is of type UTF8String and contains the identity of the NAS providing service to the user. This AVP SHOULD only be added by a RADIUS/Diameter Translation Agent. When this AVP is present, the Origin-Host AVP identifies the NAS providing service to the user. .sp In RADIUS it would be possible for a rogue NAS to forge the NAS-Identifier attribute. Diameter/RADIUS translation agents SHOULD attempt to check a received NAS-Identifier attribute against the source address of the RADIUS packet, by doing an A/AAAA RR query. If the NAS-Identifier attribute contains an FQDN, then such a query would res