RADIUS EXTensions (radext) H. Tschofenig Internet-Draft Siemens Expires: September 6, 2007 A. Mankin T. Tsenov A. Lior Bridgewater Systems J. Korhonen TeliaSonera March 5, 2007 RADIUS Quality of Service Support draft-tschofenig-radext-qos-05.txt Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. 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. 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." 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. This Internet-Draft will expire on September 6, 2007. Copyright Notice Copyright (C) The IETF Trust (2007). Tschofenig, et al. Expires September 6, 2007 [Page 1] Internet-Draft RADIUS Quality of Service Support March 2007 Abstract This document describes an extension to the RADIUS protocol that performs authentication, authorization, and accounting for Quality- of-Service reservations. The described extensions allow network elements to authenticate the initiator of a reservation request (if desired), to ensure that the reservation is authorized, and to account for established QoS resources. Flexibility is provided by offering support for different authorization models and by decoupling specific QoS attributes carried in the QoS signaling protocol from the AAA protocol. This document is the RADIUS complement to the DIAMETER QoS application. Tschofenig, et al. Expires September 6, 2007 [Page 2] Internet-Draft RADIUS Quality of Service Support March 2007 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5 3. Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4. RADIUS functional considerations . . . . . . . . . . . . . . . 7 5. Authorization and QoS parameter provision . . . . . . . . . . 8 5.1. QoS enabled initial access authentication and authorization . . . . . . . . . . . . . . . . . . . . . . 8 5.2. Mid-Session QoS authorization . . . . . . . . . . . . . . 9 5.2.1. Client-side initiated QoS authorization/re-authorization . . . . . . . . . . . . 9 5.2.2. Server-side initiated Re-Authorization . . . . . . . . 9 5.3. Session Termination . . . . . . . . . . . . . . . . . . . 10 5.3.1. Client-side initiated session termination . . . . . . 10 5.3.2. Server-side initiated session termination . . . . . . 10 6. Accounting . . . . . . . . . . . . . . . . . . . . . . . . . . 11 7. Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . 12 7.1. QoS-Resources . . . . . . . . . . . . . . . . . . . . . . 12 7.2. ExtendedQoSFilterRule . . . . . . . . . . . . . . . . . . 13 7.3. QoS-Parameter . . . . . . . . . . . . . . . . . . . . . . 15 7.4. QoS-Flow-State . . . . . . . . . . . . . . . . . . . . . . 17 7.5. Authorization Objects . . . . . . . . . . . . . . . . . . 18 8. Diameter RADIUS Interoperability . . . . . . . . . . . . . . . 20 9. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 9.1. RADIUS authorization of a QoS signaling reservation request . . . . . . . . . . . . . . . . . . . . . . . . . 21 9.2. RADIUS authentication, authorization and management of a QoS-enabled access session . . . . . . . . . . . . . . . 23 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26 11. Security Considerations . . . . . . . . . . . . . . . . . . . 27 12. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 28 13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 29 13.1. Normative References . . . . . . . . . . . . . . . . . . . 29 13.2. Informative References . . . . . . . . . . . . . . . . . . 29 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 31 Intellectual Property and Copyright Statements . . . . . . . . . . 32 Tschofenig, et al. Expires September 6, 2007 [Page 3] Internet-Draft RADIUS Quality of Service Support March 2007 1. Introduction To meet the quality-of-service needs of applications such as voice- over-IP, it will often be necessary to explicitly request resources from the network. This will allow the network to identify packets belonging to these application flows and ensure that bandwidth, delay, and error rate requirements are met. This document is a complement to the ongoing work of the DIAMETER QoS application described in [6]. It describes RADIUS protocol extensions supporting AAA in an environment where better than best effort Quality of Service is desired. The suggested extensions to the RFC 2865 [1], RFC 2866 [7], RFC 2869 [8] and RFC 3576 [9] satisfy the requirements defined in [10]. Disclaimer: The content of this document will be aligned with the ongoing QoS work in the DIME working group. Additionally, the description of the data traffic that is experiencing the QoS treatment will be aligned with the [11]. Hence, the content of the attributes presented in this document are subject to change. Tschofenig, et al. Expires September 6, 2007 [Page 4] Internet-Draft RADIUS Quality of Service Support March 2007 2. Terminology The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC-2119 [2]. Tschofenig, et al. Expires September 6, 2007 [Page 5] Internet-Draft RADIUS Quality of Service Support March 2007 3. Goals This document has a few ambitious goals, namely: o Decouple the QoS signaling protocol (such as NSIS, RSVP or link layer QoS signaling protocols) from the AAA protocol. This goal is accomplished with the help of a generic QoS description, the QSPEC object. o Support for different scenarios that demand authorization for QoS reservations. The impact is to provide flexibility with regard to the entities that trigger the QoS reservation, the QoS parameters that need to be provided to the RADIUS server for authorization, the granularity of the QoS reservation (e.g., for an individual application flow, for an aggregate). Tschofenig, et al. Expires September 6, 2007 [Page 6] Internet-Draft RADIUS Quality of Service Support March 2007 4. RADIUS functional considerations Being a value-added service, QoS provisioning SHOULD go along with explicit authorization, accounting and control over the QoS-featured user session. Specifically, the management of the authorized session with Session-Timeout(27) and Termination-Action(29) attributes raises a number of issues, identified in [12]. The solution presented in this document aims to allow explicit control by the RADIUS server (Authorizing entity) over the authorization session and its parameters. In addition, it aims to support flexible deployment scenarios of QoS authorization and parameter provisioning by Authorization entities, which know the user and its subscription profile (Home AAA server) or can provide authorization for a session requested by the user (Application server). QoS authorization and parameter provisioning MAY be incorporated into initial authentication and authorization RADIUS exchange or MAY be triggered at a later moment by a reception of a QoS signalling message. Tschofenig, et al. Expires September 6, 2007 [Page 7] Internet-Draft RADIUS Quality of Service Support March 2007 5. Authorization and QoS parameter provision 5.1. QoS enabled initial access authentication and authorization QoS enabled RADIUS client (NAS) initiates the authentication and authorization process by sending a RADIUS Access-Request to the user's Home AAA server. In addition to authentication related attributes, it includes the QSPEC(TBD) attribute, which MAY specify the QoS-Model [13] supported by the NAS and description of the currently available QoS resources or description of the QoS explicitly requested by the user. In the second case, additional session and flow identification information MIGHT be included together with the identity of the QoS authorizing application server. If the authentication process involves multiple Access-Requests (as in EAP), the RADIUS client MUST include the QSPEC(TBD) attribute and any additional QoS-authorization related information in at least the last Access-Request of the authentication process. The Home AAA server receives the Access-Request message and authenticates the user. Based on the user profile it determines the subscription QoS parameters and includes them into the QSPEC(TBD) attribute of the Access-Accept message. In case that the QoS authorization MUST be done by an Application server, which identity is included into the Access-Request message, the Home server forwards the Access-Request to the Application server. The Access-Request will contain the QSPEC(TBD) attribute and session identification information. Upon successful authorization, the Application server generates an Access-Accept containing the QSPEC(TBD) attribute, flow identification information and optionally bearer gating information. The QSPEC attribute returned to the client SHOULD contain the duration of the QoS enabled session. If the authentication or authorization of the user is not successful, the Home AAA server or the application server sends back an Access- Reject message containing Reply-Message(18) attribute with the reason for rejection. When the QoS authorization exchange completes successfully, a RADIUS Accounting session SHOULD start for reporting accounting information. Accounting information is reported as described in [7] and [8]. Loss of bearer information is reported using Access-Request message as specified in the following section. Tschofenig, et al. Expires September 6, 2007 [Page 8] Internet-Draft RADIUS Quality of Service Support March 2007 5.2. Mid-Session QoS authorization 5.2.1. Client-side initiated QoS authorization/re-authorization Two types of QoS-related events MIGHT initiate Authorize-Only Access- Request messages - reception of a QoS signaling message or expiration of authorization lifetime of ongoing QoS-enabled session. In both cases, the RADIUS client sends an Access-Request with Service-Type(6) attribute set to a value of "Authorize-Only", QSPEC(TBD) attribute and session and flow identification information. The QSPEC(TBD) attribute includes description of new QoS parameters explicitly required by the user or the QoS parameters that SHOULD be re- authorized. Session and flow (only in the re-authorization case) identification information SHOULD be the same as those used during the initial Access-Request. For example, if the User-Name(1) attribute was used in the initial Access-Request it MUST be included, especially if the User-Name(1) attribute is used to route the Access- Request to the Home RADIUS server. The "Authorize-ONLY" Access-Request MUST NOT include either User Password(2) or a CHAP Password(3). In order to protect the RADIUS message, the RADIUS client MUST include the Message-Authenticator(80) attribute. The RADIUS client will compute the value for the Message- Authenticator(80) based on [8]. The RADIUS server processes the information, including the verification of the Message-Authenticator(80) as per [8], and upon successful authorization it responds with a RADIUS Access-Accept message. It contains the Service-Type(6) attribute with value "Authorize-ONLY", the QSPEC(TBD) attribute, flow identification information and optionally bearer gating information. The QSPEC(TBD) attribute returned to the client SHOULD contain the new duration of the QoS enabled session. In case of unsuccessful authorization an Access-Reject message is sent, containing the Reply-Message(18) attribute with the reason of rejection. In case that an Application server MUST be contacted for the QoS authorization, the Home server forwards the Access-Request to the indicated Application server, which processes the QoS authorization request. 5.2.2. Server-side initiated Re-Authorization In order to take advantage of the dynamic authorization capabilities of RADIUS as defined in [9], the Authorization entity (Home or Application server) MUST be sure that the RADIUS client supports them too. An advertising approach proposed in [12] MIGHT be used.(TBD) Tschofenig, et al. Expires September 6, 2007 [Page 9] Internet-Draft RADIUS Quality of Service Support March 2007 At any time during the QoS session the RADIUS server MAY send a Change-of-Authorization (CoA) message with Service-Type(6) attribute set to value "Authorize-ONLY" and session and flow identification information. The RADIUS client MUST respond with a Change-of- Authorization NACK message with Service-Type(6) attribute with value "Authorize-ONLY" and Error-Cause(101) attribute set to value "Request-Initiated". The RADIUS client MUST then send an Access- Request containing Service-Type(6) attribute with value "Authorize- ONLY", QSPEC(TBD) attribute, session and flow identification information. This approach is compatible with the DIAMETER re- authorization procedure and is defined in RFC 3576 [9]. Furthermore, the "State" attribute SHOULD be used as specified in RFC 3576 [9]. 5.3. Session Termination 5.3.1. Client-side initiated session termination Service session MAY be related to a particular authorized QoS- provisioned data flow. In this case, session termination MAY be caused by a QoS signaling tear down message or loss of bearer report. In another scenario the service session is a QoS enabled access session, which can handle authorization of several QoS-provisioned user's data flows. In this case session termination MAY be caused by user log-off. A RADIUS client indicates session termination by sending an Accounting-Request message with Acc-Status-Type(40) attribute set to "Stop" value and final QoS related accounting records(TBD). 5.3.2. Server-side initiated session termination At anytime during a session the Authorizing Server may send a Disconnect message to terminate the session. This capability is described in detail in RFC 3576 [9]. The RADIUS server sends a Disconnect message that MUST contain identifiers that uniquely determine the subscriber's session and the RADIUS client serving that session and Service-Type(6) attribute with value "Authorize-ONLY". If the RADIUS client receives a Disconnect message, it MUST respond with the Disconnect-NACK message with Service-Type(6) attribute with value "Authorize-ONLY" and Error-Cause(101) attribute with value "Request-Initiated". If it is able to terminate the session it will send Access-Request message with Service-Type(6) attribute with value "Authorize-ONLY" and attributes for session termination. This message flow is required for compatibility with DIAMETER protocol. Also the State(24) attribute SHOULD be used as specified in RFC 3576 [9]. Tschofenig, et al. Expires September 6, 2007 [Page 10] Internet-Draft RADIUS Quality of Service Support March 2007 6. Accounting Application of the RADIUS protocol for QoS authorization presented in this document use RADIUS Accounting as defined in the RFC2865 [1], RFC2866 [7] and RFC2869 [8]. The attributes containing a QoS description and flow identification (see Section 7) are used in the accounting session for reporting the status and parameters of the provided QoS. The definition of new accounting attributes may be necessary. This aspect is for further study. After a successful QoS authorization the RADIUS client starts the corresponding accounting session by sending the Accounting-Request message. This message SHOULD contain necessary attributes to bind the current accounting session to the reported QoS session. Class(25) and Acc-Session-ID(44) attributes SHOULD be used according to [1] and [7]. The RADIUS server responds with an Accounting- Response message after successfully processing the Accounting-Request message. The Accounting-Response message MAY contain instructions for managing the accounting session, such as the Acct-Interim- Interval(85) attribute. After every successful re-authorization procedure the RADIUS client SHOULD re-initiate accounting message exchange. For indication of session termination the RADIUS client SHOULD initiate a final exchange of accounting messages with the RADIUS server. Tschofenig, et al. Expires September 6, 2007 [Page 11] Internet-Draft RADIUS Quality of Service Support March 2007 7. Attributes This section defines a QoS-Resource attribute that which consists ofthree categories of attributes: o A QoS filter rule for packet classification o QoS parameters describing requested/authorized QoS o Enumerated value stating when and how to apply the QoS-parameters to a flow. o Attributes required to carry authorization information (e.g., authorization tokens as specified in [3]) 7.1. QoS-Resources The QoS-Resources attribute is a single group attribute that can be sent in RADIUS messages to Authenticate, Authorize and provide Accounting information for QoS parameters of Flows. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TYPE | LENGTH | SUB-TYPE 1 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Extended-QoS-Filter | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Extended-QoS-Filter | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | QoS-Parameter | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | QoS-parameter | SUB-TYPE 3 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | QoS-Flow-State | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | QoS-Flow-State | SUB-TYPE 4 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Authorization-token | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type: Value of QoS-Resources Tschofenig, et al. Expires September 6, 2007 [Page 12] Internet-Draft RADIUS Quality of Service Support March 2007 Length: variable, greater than 8 String: The String value MUST be encoded as follows: Sub-Type (=1): Sub-Type for Extended-QoS-Filter Length : variable, greater than 8 String : The Extended-QoS-Filter rule is a string type defined in Section 7.2 Sub-Type (=2): Sub-Type for QoS-Parameter Length : variable, greater than 8 String : The QoS-Parameter is a string type defined in Section 7.3 Sub-Type (=3): Sub-Type for QoS-Flow-State Length : variable, greater than 8 String : The QoS-Flow-State rule is a string type defined in Section 7.4 Sub-Type (=4): Sub-Type for Authorization-Token Length : variable, greater than 8 String : The Authorization-Token is a string type defined in Section 7.5 7.2. ExtendedQoSFilterRule The Extended QoS filter rule parameter is based on [4] and is used as a packet classifier. Tschofenig, et al. Expires September 6, 2007 [Page 13] Internet-Draft RADIUS Quality of Service Support March 2007 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TYPE | LENGTH | SUB-TYPE 1 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Extended-QoS-Filter-Value | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Extended-QoS-Filter-Value | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type: Value of Extended-QoS-filter-Value Length: variable, greater than 8 String: The String value uses the ASCII charset. It MUST follow the format: The ExtendedQoSFilterRule is an OctetString. It uses the ASCII charset. The ExtendedQoSFilterRule MUST follow the format: Tschofenig, et al. Expires September 6, 2007 [Page 14] Internet-Draft RADIUS Quality of Service Support March 2007 action dir proto from src to dst [options] Labels Description action Action associated with the packet treatment. Basic actions are described in the IPFilterRule and extended for usage with QoS treatment. dir Direction of the packet follow the filter applies to. A basic description can be found with the IPFilterRule. Examples are in, out and both. proto Protocol A description can be found with the IPFilterRule. src and dst
[ports] A description can be found with the IPFilterRule. flow-label IPv6 Flow Label A description can be found in TBD. dscp Diffserv Codepoints A description can be found in TBD. ipsec-spi IPsec Security Parameter Index (SPI) A description can be found in TBD. qos-id A unique id referencing the applicable QoS parameters that need to be applied to the specified packets. 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. 7.3. QoS-Parameter The generic QoS description is taken from [5] which aims to support QoS parameters for all QoS reservations and is independent of a specific QoS model (QOSM). The QoS-Parameter template format is identified by a qoS-Id value and has QSPEC parameters in it. These QSPEC parametrs are organized into QoS Control information, Requested, Reserved, Available and Minimum objects. QoS-Id and QSPEC parameters are are included as subtypes into the QSPEC attribute. Subtypes not used are omitted in the message. Tschofenig, et al. Expires September 6, 2007 [Page 15] Internet-Draft RADIUS Quality of Service Support March 2007 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TYPE | LENGTH | SUB-TYPE 1 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | QoS-ID | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TMOD Rate-1 [r] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SUB-TYPE 2 | LENGTH | TMOD Size-1 [b] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TMOD Size-1[b] | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peak Data Rate-1 [p] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SUB-TYPE 2 | LENGTH | Minimum policed unit-1 [m] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Minimum policed unit-1 [m] | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TMOD Rate-2 [r] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SUB-TYPE 2 | LENGTH | TMOD Size-2 [b] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TMOD Size-2[b] | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peak Data Rate-2 [p] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SUB-TYPE 2 | LENGTH | Minimum policed unit-2 [m] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Minimum policed unit-2 [m] | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Path Latency | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SUB-TYPE 2 | LENGTH | Path Jitter STAT1 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Path Jitter STAT1 | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Path Jitter STAT2 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SUB-TYPE 2 | LENGTH | Path Jitter STAT3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Path Jitter STAT3 | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Path Jitter STAT4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SUB-TYPE 2 | LENGTH | Path Packet Loss Ratio | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Path Packet Loss Ratio | SUB-TYPE 2 | LENGTH | Tschofenig, et al. Expires September 6, 2007 [Page 16] Internet-Draft RADIUS Quality of Service Support March 2007 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Path Packet Error Ratio | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SUB-TYPE 2 | LENGTH | Slack Term | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Slack Term | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Preemption prioroty | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Defending priority | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Admission Priority | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SUB-TYPE 2 | LENGTH | RPH Namespace | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | RPH Priority | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Excess Treatment Parameter | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SUB-TYPE 2 | LENGTH | PHB Class Parameter | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PHB Class Parameter | SUB-TYPE 2 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |DSTE Class Type Parameter | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SUB-TYPE 2 | LENGTH | Y.1541 QoS Class | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Y.1541 QoS Class | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The above-mentioned attributes are defined in [5] and the list of parameters mentioned SHOULD be updated according to [5]. 7.4. QoS-Flow-State The QoS-Flow-State gives an indication by the Authorizing entity as to how the flow MUST be treated. When included in an Access-Request message, it contains an action to be performed on the state of the flow to which the message applies. It is of type Enumerated. TBD Tschofenig, et al. Expires September 6, 2007 [Page 17] Internet-Draft RADIUS Quality of Service Support March 2007 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TYPE | LENGTH | SUB-TYPE 1 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | QoS-flow-State | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type: Enumerated Length : Length of QoS-Flow-State attribute (= 4 octets) QoS-Flow-State: 0 Open - Enable the transport plane service, for which the signaling has been performed. 1 Close - Disable the transport plane service 2 Maintain - Do not alter the current state (enabled/disabled) of the transport plane service. The QoS-Flow-State is optional. When not included in a Access- Accept response, the default behavior is to immediately allow the flow of packets (Open). The behavior of Close (0) for the QoS-Flow-State refers to the case where a QoS reservation exists but it is not activated and therefore not charged. For time-based charging the time interval where the gate is closed will not be included of the chargeable time interval. The QoS model might give some indication whether an established QoS reservation needs to be freed or needs to be removed only if not enough resources are available. 7.5. Authorization Objects Depending on the deployment, different attributes MAY be used as an input for computing the QoS authorization decision by the Authorizing entity. In addition to the credentials of the end host, requesting QoS reservation (e.g., User-Name(1) attribute), an authorization token MAY be used. This occurs in a deployment scenario, where the QoS parameters are negotiated as part of an application layer signaling exchange and where the authorization decision at this application layer exchange needs to be associated with the authorization of the QoS reservation of the QoS signaling exchange. The QoS-Authorization-Data attribute is designated to encapsulate such information. Tschofenig, et al. Expires September 6, 2007 [Page 18] Internet-Draft RADIUS Quality of Service Support March 2007 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TYPE | LENGTH | SUB-TYPE 1 | LENGTH | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Authorization-Token | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type : Value of QoS-Authorization-Data Length: variable, greater than 8 String: The String value MUST be encoded as follows: Sub-Type (=1): Authorization-Token Length : Length of Authorization-Token attribute Authorization-Token: The Authorization-Token sub-attribute is a container that encapsulates an authorization token received via the QoS signaling message typically sent by the end host. The token is generated by the Authorizing entity during the application layer signaling exchange and identifies the application service session, for which the QoS reservation request applies. A possible structure for the authorization token is proposed in context of RSVP [3] or using SAML as outlined in [14] and [15]. The structure of the token is considered to be out of the scope for this document. Tschofenig, et al. Expires September 6, 2007 [Page 19] Internet-Draft RADIUS Quality of Service Support March 2007 8. Diameter RADIUS Interoperability In deployments where RADIUS clients communicate with DIAMETER servers or DIAMETER clients communicate with RADIUS servers then a translation agent will be deployed and operate. The DIAMETER-QoS specification [6] provides a natural candidate for mapping the RADIUS QoS related AVPs to DIAMETER AVPs and messages. Tschofenig, et al. Expires September 6, 2007 [Page 20] Internet-Draft RADIUS Quality of Service Support March 2007 9. Examples The following diagrams show RADIUS protocol interactions for different scenarios and deployment architectures. 9.1. RADIUS authorization of a QoS signaling reservation request Tschofenig, et al. Expires September 6, 2007 [Page 21] Internet-Draft RADIUS Quality of Service Support March 2007 RADIUS RADIUS Client Server -----------> | | QoS | Access-Request/UserID, QSPEC/ | reservation |----------------------------------------------->| request | | | Access-Accept/QSPEC/ | |<-----------------------------------------------| | | Start |Accounting-Request/Start, Acc-Session-ID.../ | Accounting |----------------------------------------------->| | Accounting-Response/...Acc-Interim-Period.../ | |<-----------------------------------------------| | | Authorization| | LifeTime | | Expires: | | Re- | Access-Request/Auth-ONLY, UserID, QSPEC/ | Authorization|----------------------------------------------->| | Access-Accept/ Auth-ONLY, QSPEC/ | |<-----------------------------------------------| | Accounting-Request/Interim, Acc-Session-ID./ | |----------------------------------------------->| | Accounting-Response/...Acc-Interim-Period.../ | |<-----------------------------------------------| ..................... | Session | Termination | initiated | by | server | Disconnect-Request/Auth-ONLY, .../ <------ |<-----------------------------------------------| | Disconnect-NACK/Auth-ONLY,"Request-Initiated"/ | |----------------------------------------------->| | Access-Request/Auth-ONLY,... | | Acc-Terminate-Cause="Admin-Reset"/| |----------------------------------------------->| | Access-Accept | |<-----------------------------------------------| Accounting | Accounting-Request/Final,Acc-Session-ID./ | end |----------------------------------------------->| | Accounting-Response /Final,.../ | |<-----------------------------------------------| This example shows the protocol exchange between the RADIUS client and the RADIUS server. An incoming QoS reservation request received at the QoS policy aware node (i.e., RADIUS client) invokes the Tschofenig, et al. Expires September 6, 2007 [Page 22] Internet-Draft RADIUS Quality of Service Support March 2007 transmission of a Access-Request message (AR) to the RADIUS server. This message contains the requested QoS resources in a QSPEC attribute along with user identification and authentication information. After the request is successfully authenticated and authorized, the RADIUS server replies with a Access-Accept message (AA), which grants a reservation for a certain amount of resources (as included in the QSPEC attribute). After the successful exchange of the AR/AA messages, the RADIUS client starts an accounting session by sending an Accounting-Request message. The server replies with an Accounting-Response message that MAY include instructions for further handling of the accounting session, such as the Acc-Interim-Period attribute. The client-side re-authorization caused by expiration of the authorization lifetime initiates an Authorize-ONLY Access-Request / Access-Accept message exchange. After a successful re-authorization an Accounting-Request message SHOULD be sent to indicate the new authorization parameters. The server replies with an Accounting- Response message. In this example, the RADIUS server initiates a session termination. It therefore sends a Disconnect-Request message. The client responds with a Disconnect-NACK message and sends an AR message indicating the termination cause. The server replies to the AR message with an AA message. After receiving the AA message sent by the server, the client sends remaining accounting information with the Accounting- Request message. The server replies with the Accounting-Response message. 9.2. RADIUS authentication, authorization and management of a QoS- enabled access session QoS enabled NAS Home RADIUS client RADIUS server | | | Access-Request/....QSPEC(QoS Available) .../ | v----------------------------------------------->| * | * Multiple | Authentication *<==============================================>| process * Access-Request/Access-Challenge Exchange | * | * | Access granted; * Access-Accept/...QSPEC(user-profile QoS).../| install QoS v<-----------------------------------------------| | | | Accounting-Request/...QSPEC(installed QoS)../ | Tschofenig, et al. Expires September 6, 2007 [Page 23] Internet-Draft RADIUS Quality of Service Support March 2007 |----------------------------------------------->| | Accounting-Response/.../ | |<-----------------------------------------------| | | | | QoS-Request | Access-Request/Auth-ONLY, QSPEC, QoS-Flow-ID/ | --------------->|----------------------------------------------->| | Access-Response/Auth-ONLY, QSPEC, QoS-Flow-ID/| QoS authorized; *<-----------------------------------------------| install QoS for | | QoS-Flow-ID | | | Accounting-Request/Interim,.../ | |----------------------------------------------->| | Accounting-Response/.../ | |<-----------------------------------------------| .............................................................. | | * | QoS-Flow-ID authz.lifetime expires | Delete QoS for QoS-Flow-ID | | | | Accounting-Request/Interim,.../ | |----------------------------------------------->| | Accounting-Response/.../ | |<-----------------------------------------------| .............................................................. | | | CoA-Request /Auth-ONLY,QSPEC.../ | |<-----------------------------------------------| | CoA-NACK/Auth-ONLY,"Request-Initiated"/ | |----------------------------------------------->| | Access-Request/Auth-ONLY,QSPEC.../ | |----------------------------------------------->| | Access-Accept/Auth-ONLY,QSPEC(New QoS).../ | Install QoS *<-----------------------------------------------| | | | Accounting-Request/...QSPEC(installed QoS)../ | |----------------------------------------------->| | Accounting-Response/.../ | |<-----------------------------------------------| This example shows the interaction between a QoS enabled NAS and a Home AAA server. This example aims to show a QoS-enabled access session. The NAS performs authorization of the QoS-provisioned flows as part of the user's access session. The NAS performs initial authentication and authorization of the end user for an access session. This process MAY take several Access- Tschofenig, et al. Expires September 6, 2007 [Page 24] Internet-Draft RADIUS Quality of Service Support March 2007 Request / Access-Challenge message exchanges. By including the QSPEC attribute, the RADIUS server provides a description of the QoS parameters of the user access session. The NAS allocates certain QoS resources according to the QoS parameters provided by the RADIUS server and currently available QoS resources. The NAS initiates an accounting session by sending the Accounting-Request message in which it reports the actually allocated QoS resources for the access session. The server replies with an Accounting-Response message that MAY include instructions for further handling of the accounting session, such as the Acc-Interim-Period attribute. Later, when the NAS intercepts a QoS signaling message sent from the end host an Authorize-ONLY Access-Request message is triggered and sent to the RADIUS server. It includes the description of the requested QoS resources in the QSPEC attribute. Optionally, an identifier of the flow that should receive the requested QoS treatment is included into the Access-Request message. The RADIUS server (in the user's home domain) validates the QoS request and replies with Authorize-ONLY Access-Accept message. The message includes a QSPEC attribute with description of the authorized QoS parameters and the duration of authorization. An identifier of the flow that should receive the requested QoS is also provided. The RADIUS client will install a QoS reservation based on the provided QoS parameters for that flow and sends an Accounting-Request message reporting the new QoS session. The server replies with an Accounting-Response message. In this example, the authorization lifetime of the QoS-provisioned flow expires. The NAS releases the reserved QoS resources allocated for the flow when the authorization has expired. In addition, the NAS sends an Accounting-Request message to the RADIUS server, indicating the stop of QoS provisioning for the flow. If the Home AAA server decides to change QoS parameters for the user's access session it sends an Authorize-ONLY Change-of- Authorization-Request message to the RADIUS client, identifying the affected access session. The NAS replies with a CoA-NACK message indicating that an Access-Request has to be generated. The Authorize-ONLY Access-Request message contains the QSPEC attribute with the QoS resources currently available at the NAS. The RADIUS server replies with the Authorize-ONLY Access-Accept message with a QSPEC attribute containing the new QoS parameters that should be provided to the user's session. The NAS allocates certain QoS resources according to the QoS parameters provided by the RADIUS server and the currently available QoS resources. It sends an Accounting-Request message in which it reports the actual allocated QoS resources for the access session. The server replies with an Accounting-Response message. Tschofenig, et al. Expires September 6, 2007 [Page 25] Internet-Draft RADIUS Quality of Service Support March 2007 10. IANA Considerations TBD Tschofenig, et al. Expires September 6, 2007 [Page 26] Internet-Draft RADIUS Quality of Service Support March 2007 11. Security Considerations For this extension to RADIUS protocol the security considerations defined in RFC2865 [1], RFC2866 [7], RFC2869 [8] and RFC3576 [9] are applicable. Furthermore, the security of the QoS signaling protocol and the QoS authorization framework must be considered in the evaluation of the security properties. [Editor's Note: A more detailed treatment will be provided in a future document version.] Tschofenig, et al. Expires September 6, 2007 [Page 27] Internet-Draft RADIUS Quality of Service Support March 2007 12. Acknowledgments We would like to thank Pete McCann and Franck Alfano for their work on the Diameter QoS application. Tschofenig, et al. Expires September 6, 2007 [Page 28] Internet-Draft RADIUS Quality of Service Support March 2007 13. References 13.1. Normative References [1] Rigney, C., Willens, S., Rubens, A., and W. Simpson, "Remote Authentication Dial In User Service (RADIUS)", RFC 2865, June 2000. [2] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", March 1997. [3] Hamer, L-N., Gage, B., Kosinski, B., and H. Shieh, "Session Authorization Policy Element", RFC 3520, April 2003. [4] Zorn, G., McCann, P., Tschofenig, H., Tsou, T., and A. Doria, "Diameter Quality of Service Application", draft-ietf-dime-diameter-qos-00.txt (work in progress), February 2006. [5] Korhonen, J. and H. Tschofenig, "Quality of Service Parameters for RADIUS and Diameter", draft-korhonen-dime-qos-parameters-00.txt (work in progress), February 2006. 13.2. Informative References [6] Alfano, F., "Diameter Quality of Service Application", draft-tschofenig-dime-diameter-qos-01 (work in progress), October 2006. [7] Rigney, C., "RADIUS Accounting", RFC 2866, June 2000. [8] Rigney, C., Willats, W., and P. Calhoun, "RADIUS Extensions", RFC 2869, June 2000. [9] Chiba, M., Dommety, G., Eklund, M., Mitton, D., and B. Aboba, "Dynamic Authorization Extensions to Remote Authentication Dial In User Service (RADIUS)", RFC 3576, July 2003. [10] Alfano, F., "Requirements for a QoS AAA Protocol", draft-alfano-aaa-qosreq-01 (work in progress), October 2003. [11] Congdon, P., "RADIUS Filter Rule Attribute", draft-ietf-radext-filter-08 (work in progress), January 2007. [12] Lior, A., "Prepaid extensions to Remote Authentication Dial-In User Service (RADIUS)", draft-lior-radius-prepaid-extensions-11 (work in progress), June 2006. Tschofenig, et al. Expires September 6, 2007 [Page 29] Internet-Draft RADIUS Quality of Service Support March 2007 [13] Ash, J., "QoS NSLP QSPEC Template", draft-ietf-nsis-qspec-15 (work in progress), February 2007. [14] Peterson, J., "Trait-based Authorization Requirements for the Session Initiation Protocol (SIP)", draft-ietf-sipping-trait-authz-02 (work in progress), January 2006. [15] Tschofenig, H., "SIP SAML Profile and Binding", draft-ietf-sip-saml-01 (work in progress), October 2006. Tschofenig, et al. Expires September 6, 2007 [Page 30] Internet-Draft RADIUS Quality of Service Support March 2007 Authors' Addresses Hannes Tschofenig Siemens Otto-Hahn-Ring 6 Munich, Bavaria 81739 Germany Email: Hannes.Tschofenig@siemens.com URI: http://www.tschofenig.com Allison Mankin 1025 Vermont Avenue Washington, DC 20005 US Phone: +1 301-728-7199 (mobile) Email: mankin@psg.com URI: http://www.psg.com/~mankin/ Tseno Tsenov Sofia, Bulgaria Email: tseno.tsenov@mytum.de Avi Lior Bridgewater Systems Corporation 303 Terry Fox Drive Ottawa, Ontario K2K 3J1 Canada Phone: +1 613-591-6655 Email: avi@bridgewatersystems.com Jouni Korhonen TeliaSonera Teollisuuskatu 13 Sonera FIN-00051 Finland Email: jouni.korhonen@teliasonera.com Tschofenig, et al. Expires September 6, 2007 [Page 31] Internet-Draft RADIUS Quality of Service Support March 2007 Full Copyright Statement Copyright (C) The IETF Trust (2007). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Intellectual Property The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Acknowledgment Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA). Tschofenig, et al. Expires September 6, 2007 [Page 32]