PANA Working Group L. Morand Internet-Draft France Telecom R&D Intended status: Informational R. Maglione Expires: March 18, 2007 Telecom Italia J. Kaippallimalil Huawei Technologies A. Yegin Samsung September 14, 2006 Application of PANA framework to DSL networks draft-morand-pana-panaoverdsl-00 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 March 18, 2007. Copyright Notice Copyright (C) The Internet Society (2006). Abstract This document provides guidelines for PANA deployment over DSL access networks. The document specifically describes the introduction of PANA in DSL networks migrating from a traditional PPP access model to Morand, et al. Expires March 18, 2007 [Page 1] Internet-Draft PANA over DSL networks September 2006 a pure IP-based access environment. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Specification of Requirements . . . . . . . . . . . . . . . . 3 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. PANA Framework Overview . . . . . . . . . . . . . . . . . . . 3 5. PANA in DSL environment . . . . . . . . . . . . . . . . . . . 4 5.1. Evolution of DSL Environment . . . . . . . . . . . . . . . 4 5.2. Advisability of Introducing PANA in DSL Environment . . . 5 6. Applicability of PANA to IP Session based DSL Environment . . 7 6.1. Functional Architecture . . . . . . . . . . . . . . . . . 7 6.1.1. Location of PAA and EP . . . . . . . . . . . . . . . . 7 6.1.2. Location of the PaC . . . . . . . . . . . . . . . . . 8 6.2. IP Address Configuration . . . . . . . . . . . . . . . . . 9 6.3. PANA and Dynamic ISP Selection . . . . . . . . . . . . . . 10 6.3.1. Selection as Part of the DHCP protocol or an Attribute of DSL Access Line . . . . . . . . . . . . . 11 6.3.2. Selection as Part of the PANA Authentication . . . . . 11 6.4. Cryptographic Protection . . . . . . . . . . . . . . . . . 11 6.5. Example of Basic Flows . . . . . . . . . . . . . . . . . . 11 7. Security Considerations . . . . . . . . . . . . . . . . . . . 13 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 8.1. Normative References . . . . . . . . . . . . . . . . . . . 13 8.2. Informative References . . . . . . . . . . . . . . . . . . 14 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15 Intellectual Property and Copyright Statements . . . . . . . . . . 17 Morand, et al. Expires March 18, 2007 [Page 2] Internet-Draft PANA over DSL networks September 2006 1. Introduction PANA (Protocol for carrying Authentication for Network Access) design provides support for various types of deployments. DSL networks were identified as a typical example of such a deployment. This document provides guidelines for PANA deployment over DSL access networks. The document specifically describes the introduction of PANA in DSL networks migrating from a traditional PPP access model to a pure IP- based access environment. In such environment, additional authentication mechanisms are required to provide a complete secure network access solution to Network Access Providers (NAP) willing to overtake inadequate methods such as basic DSL link-layer identification or application-layer ad-hoc authentication mechanisms (e.g., HTTP redirects with web-based login). 2. Specification of Requirements 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 [RFC2119]. 3. Terminology This document uses the PANA terminology defined in [I-D.ietf-pana-pana]. This document uses the DSL Forum terminology defined in [TR25], [TR59] and [WT146]. 4. PANA Framework Overview PANA (Protocol for carrying Authentication for Network Access) is a link-layer agnostic transport for EAP [RFC3748] to enable network access authentication between clients and access networks. The motivation to define such a protocol and the requirements are described in [RFC4058]. Protocol details are documented in [I-D.ietf-pana-pana]. There are components that are part of a complete secure network access solution but are outside of the PANA protocol specification, including IP address configuration, authentication method choice, filter rule installation, data traffic protection, PAA-EP protocol and PAA discovery. These components except for IP address configuration (see Appendix A of [I-D.ietf-pana-pana]) are described in separate documents (see [I-D.ietf-pana-framework], [I-D.ietf-pana-snmp] and [I-D.ietf-dhc-paa-option]. Morand, et al. Expires March 18, 2007 [Page 3] Internet-Draft PANA over DSL networks September 2006 Figure 1 illustrates the functional entities involved in the PANA framework and the interfaces (protocols, APIs) among them. See [I-D.ietf-pana-pana] and [I-D.ietf-pana-framework] for further details. RADIUS/ Diameter/ +-----+ PANA +-----+ LDAP/ API +-----+ | PaC |<----------------->| PAA |<---------------->| AS | +-----+ +-----+ +-----+ ^ ^ | | | +-----+ | IKE/ +-------->| EP |<--------+ SNMP/ API 4-way handshake +-----+ Figure 1: PANA Functional Model PaC: PANA Client PAA: PANA Authentication Agent AS: Authentication Server EP: Enforcement Point PANA design provides support for various types of deployments. DSL networks were identified as a typical example of such a deployment (see Appendix A of [RFC4058]). 5. PANA in DSL environment 5.1. Evolution of DSL Environment Traditional DSL deployments followed the architectural guidelines provided in [TR25] or [TR59]. Theses architectures use ATM to aggregate the access networks into a regional broadband network. The traffic aggregated from the access nodes (DSLAM) is steered to an IP node, the Broadband Remote Access Server (BRAS). In this environment, PPP sessions are set-up between the CPN (Customer Premises Network) and the BRAS, which acts as either a PPP termination point or a L2TP Access Concentrator (LAC) tunnelling multiple subscriber PPP sessions directly to an Internet/Corporate Service Provider. The CPN is usually defined as the combination of the DSL Modem/RG, acting as the termination point of the physical DSL signal, and the subscriber's computers and other devices (named hosts hereafter) connected to the DSL Modem/RG. Morand, et al. Expires March 18, 2007 [Page 4] Internet-Draft PANA over DSL networks September 2006 Host--+ +-- ISP1 | DSL link | +-- DSL Modem/RG --- DSLAM --- BRAS --+-- ISP2 | | Host--+ +-- ISP3 <-------- CPN --------> <------ NAP ------> <-- ISP --> Figure 2: DSL Model The devices at the customer premises have been shown as "hosts" in the above network. DSL architectures are now emerging from a "low" speed best effort delivery network to an infrastructure capable of supporting higher subscriber bit rates. At the application layer, DSL service providers are looking to support enhanced services layered on top of basic Internet access, including entertainment video services (Broadcast TV and VoD), video conferencing, VoIP, gaming, and business class services (e.g. IP VPN), that have prohibitive requirements to deploy them in a pure ATM based environment. Moving to on a Gigabit Ethernet instead of an ATM aggregation network offers an highly efficient transport technology for delivering large amounts of bandwidth to a highly distributed access node topology. In this evolution path towards Giga Ethernet, there is in parallel a growing interest in migrating from the traditional PPP access model to one relying on an network access control of IP sessions establishment. The "IP Sessions" model is a concept introduced in DSL Forum that covers a cycle consisting of IP session Detection and creation, application of IP session policies, and IP session termination. Details of this work are documented in [WT146]. Basically, an IP session represents subscriber IP traffic which is associated with a subscriber's IP address parameters. A subscriber may have multiple IP addresses (or sessions) in simultaneous use. An IP session may in turn be associated with multiple IP flows. The relation between subscribers and policies associated with it are described in [WT134]. The policy relationships in this document show that subscribers have services that are governed by policies. Thus, the same subscriber policies govern all IP sessions/flows belonging to the subscriber. 5.2. Advisability of Introducing PANA in DSL Environment Among other challenges for DSL environment migrating from pure PPP based networks, one is the need for the creation of an IP session subscriber authentication model to secure network access and IP address management provided by a DHCP infrastructure. Indeed, Morand, et al. Expires March 18, 2007 [Page 5] Internet-Draft PANA over DSL networks September 2006 contrary to PPP environment, an IP sessions model has no built-in mechanisms for authentication purposes in a DHCP based environment. Hence additional mechanisms are required to provide Network Access Providers (NAP) with an explicit access authentication solution. Providing a native support of EAP frames over IP, PANA is therefore a natural candidate to provide the protocol support of an IP subscriber authentication model. Moreover, PANA provides functionalities fulfilling basic and advanced security requirements within an IP session based environment (as described in [WT146]) , such as: o IP address based session management mechanisms, using an explicit session identifier; o Authentication mechanism independent of the physical medium type; o Per-session enforcement policies (i.e. filters) depending on the creation and deletion of the PANA session; o Session keep-alive and session monitoring functionalities. In this new context for DSL networks, PANA may be introduced to authenticate the credentials of a user prior to the setup of an IP session. The user selects the service provider and authenticates itself. During IP session setup, policies for the use of connection resources related to the IP session are established in the BRAS. These policies govern the subscriber's use of network resources. IP flows are accounted for and associated with the IP session and the service session that triggered it. Some examples to illustrate use cases for PANA in the DSL IP Session model are given below: o A user has an intelligent terminal (e.g. smart phone) that is able to provide both voice and data services. In this case, the user has subscribed two services e.g. VoIP and Internet. Following a PANA authentication, an IP session is created based on the single IP address allocated to the terminal. However it is possible to distinguish two distinct IP flows within the same IP session, one for each service, and the accounting policy may be different for theses two flows. The service provider is therefore able to associate the accounting records to each flow within the same IP session in order to bill the two services according to the subscribed rates. o A user has subscribed to two services in addition to Internet access e.g. VoIP and IP TV. Each of these services has a Morand, et al. Expires March 18, 2007 [Page 6] Internet-Draft PANA over DSL networks September 2006 dedicated host associated with it. The hosts authenticate on behalf of the subscriber. After successful multiple PANA authentications (one per host), a distinct IP address is allocated to each of these hosts. Thus, there are at this point three IP sessions related to the same IP subscriber. The VoIP and IP TV flows may be provided a differentiated level of quality. Corresponding accounting records and their association with the service sessions need to be maintained for billing and settlement. o A user starts a session in one network, authenticates using PANA and starts using a network service. At some point in time, the user moves to another network (i.e., continues the session in another network). In this case, there are two IP sessions (that results subsequent to PANA authentication in first network, and PANA authentication in second network) used during the course of the same service session. Accounting (in the service provider) should be able to associate the flows related to the two IP sessions (from different networks) with the same service session. 6. Applicability of PANA to IP Session based DSL Environment 6.1. Functional Architecture 6.1.1. Location of PAA and EP In a PPP based environment, the BRAS is in charge of interfacing with CPE for authenticating and authorizing them for the network access service as well as performing policy control by acting as en enforcement point. In an IP session based environment, such functionalities may be provided at the same level by locating the PAA and EP entities in the BRAS. One advantage provided by this implementation is to preserve a improved and well-established DSL network configuration. Moreover, PAA and EP being collocated, there is no need to rely on an external interface between them to carry the authorized client attributes i.e. filters, an API being sufficient in that case. However, it is possible to have PAA and BRAS/EP not collocated, as described in [I-D.ietf-pana-framework]. In that specific case, a PAA-BRAS interface may be based on SNMP (see [I-D.ietf-pana-snmp]) or on the future ANCP protocol (see charter of the ANCP IETF Working Group [www.ietf.org/html.charters/ ancp-charter.html]). In such a configuration, the PAA will have to verify the credentials provided by a PaC located in the CPN and authorize network access to the host associated with the client and identified by a Device Identifier (DI). Morand, et al. Expires March 18, 2007 [Page 7] Internet-Draft PANA over DSL networks September 2006 As described in [WT146], the subscriber IP address is the main mean of classifying and managing an IP subscriber session. Therefore, despite the fact that a link-layer identifier (e.g. MAC address) may be used in some cases, the subscriber IP address will have to be the Device Identifier (DI) used in PANA by PAA/EP as a handle to control and police the network access. The host in CPN that can be authenticated by the PAA, and therefore where the PaC should be implemented, will be determined by the operation mode of the DSL Modem/RG, which may act as either a Layer-2 Ethernet bridge (Bridged Mode) or a Layer-3 IP router (Routed Mode). 6.1.2. Location of the PaC 6.1.2.1. Bridged Mode In the Bridged mode, the DSL Modem/RG acts as a simple link-layer bridge. The DSL Modem/RG is here transparent at the IP layer. The hosts (e.g. PC) connected to the DSL Modem/RG in the CPN and the BRAS are then on the same IP link. Hosts may have a statically configured IP address or obtain an IP address from a DHCP server through the DSLAM (acting as a DHCP-Relay agent) and the BRAS (filtering DHCP requests towards the DHCP server). In this model, the PaC can be easily implemented in the hosts. Any host connected to the DSL Modem/RG will be authenticated by the PAA locating in the BRAS. It is therefore possible to perform a network access control on a per-host basis, as required by the IP session model. Host--+ (PaC) | +-- DSL Modem/RG --- DSLAM --- BRAS ----- ISP | (Bridge) (PAA,EP) Host--+ (PaC) Figure 3: Bridged Mode 6.1.2.2. Routed Mode In the Routed mode, the DSL Modem/RG acts as an IP router for the CPN. In this configuration, only the DSL Modem/RG and BRAS are on the same IP link. The DSL Modem/RG may have a statically configured IP address or obtain an IP address from a DHCP server through the DSLAM (acting as a DHCP-Relay agent) and the BRAS (filtering DHCP requests towards the DHCP server). Hosts connected to the DSL Modem/RG may use either (1) either private IP addresses in an IPv4 environment with the DSL Modem/RG implemented a Network Address Port Morand, et al. Expires March 18, 2007 [Page 8] Internet-Draft PANA over DSL networks September 2006 Translation (NAPT) function or (2) routable IP addresses if the modem is an IPv6 router. In the IPv4 context (1), the simplest method is to implement the PaC in the DSL Modem/RG. Only the DSL Modem/RG will be authenticated/ authorized by the PAA. All hosts at the customer premises will then have access to the service provider's network using private IP addresses obtained from the DSL Modem/RG. (NOTE: Per-host authentication may be achieve also in the Routed mode if the EP function is performed by the DSL Modem/RG. However it is for further studies to see how to introduce such a configuration in the global DSL Forum "IP Sessions" model.) In the IPv6 case (2), the BRAS will detect any new IP address used by the DSL Modem/RG and the hosts connected to the DSL Modem/RG if they use an non-local IP address. To allow a suitable network access rights management based on the IP address, PANA clients will have to be therefore implemented in the DSL Modem/RG and the hosts. As in the Bridged Mode, the network access control is also performed on a per-host basis, in addition to the handling of the DSL Modem/RG 's own IP sessions. Host--+ | +-- DSL Modem/RG --- DSLAM --- BRAS ----- ISP | (Router, PaC) (PAA,EP) Host--+ IPv4 Case (1) Host--+ (PaC) | +-- DSL Modem/RG --- DSLAM --- BRAS ----- ISP | (Router, PaC) (PAA,EP) Host--+ (PaC) IPv6 Case (2) Figure 4: Routed Mode 6.2. IP Address Configuration As described in [I-D.ietf-pana-framework], the PaC MUST obtain an IP address prior to performing PANA-based authentication, called pre- PANA address (PRPA). In the context of PANA deployment in DSL environment based on the IP Sessions model, the PRPA MAY be configured by the following methods: Morand, et al. Expires March 18, 2007 [Page 9] Internet-Draft PANA over DSL networks September 2006 1. The PaC MAY be statically configured with an IP address. This address is therefore used as a PRPA. 2. The PaC MAY dynamically configure the PRPA using DHCPv4 [RFC2131] or DHCPv6 [RFC3315]. 3. In IPv6, the PaC MAY also configure non-link-local address(es) using IPv6 stateless auto-configuration [RFC2461] if router advertisements with prefixes are made available. (NOTE: PANA supports also hosts using IPv4 link-local addresses [RFC3927] as PRPA. However, at this time, it is not clear if such IP address configuration is supported in the DSL Forum "IP Sessions" model.) After a successful authentication, the PaC MAY have to configure a new IP address for communication with other nodes if the PRPA is a local-use (e.g., a link-local or private address) or a temporarily allocated IP address. This IP address is called a post-PANA address (POPA). An operator might choose allocating a POPA only after successful PANA authorization either to prevent waste of premium (e.g., globally routable) IP resources until the PaC is authorized (especially in the IPv4 case), or to enable PaC identity based address assignment. POPA can be configured using DHCP [RFC2131] [RFC3315] or using IPv6 stateless auto-configuration [RFC2461]. See Appendix A of [I-D.ietf-pana-pana] for further details on IP address configuration. 6.3. PANA and Dynamic ISP Selection In some installations, a BRAS is shared by multiple service providers. Each service provider configures the BRAS with a specific IP address space. The hosts at the customer premises network indicate their choice of service provider and the BRAS chooses the IP address from the appropriate service provider's pool. In many cases, the address is assigned not by the BRAS but by the AAA server that is managed fully by the service provider. This simplifies the management of the DSL access network as it is not always necessary to configure each DSL access line with the service provider's identity. The service provider is chosen dynamically by the DSL Modem/RG. This is typically known as "dynamic Internet Service Provider selection". The AAA function is usually overloaded to perform dynamic ISP selection. Morand, et al. Expires March 18, 2007 [Page 10] Internet-Draft PANA over DSL networks September 2006 6.3.1. Selection as Part of the DHCP protocol or an Attribute of DSL Access Line The ISP selection, therefore the IP address pool, can be conveyed based on the DHCP protocol exchange using, e.g., the 'client-id' field of a DHCP packet, or by associating the DSL access line to the service provider before the PANA authentication begins. When any of these schemes is used, the IP address used during PANA authentication (PRPA) is the ultimate IP address and it does not have to be changed upon successful authorization. 6.3.2. Selection as Part of the PANA Authentication The ISP selection of the client can be explicitly conveyed during the PANA authentication (see "Network Selection" in [I-D.ietf-pana-pana]). In that case, the client can be assigned a temporary IP address (PRPA) prior to PANA authentication. This IP address might be obtained via DHCP with a lease reasonably long to complete PANA authentication, or via stateless auto-configuration. In either case, successful PANA authentication signalling prompts the client to obtain a new (long term) IP address via DHCP. This new IP address (POPA) replaces the previously allocated temporary IP address. 6.4. Cryptographic Protection DSL networks are protected by physical means. Eavesdropping and spoofing attacks are prevented by keeping the unintended users physically away from the network media. Therefore, generally cryptographic protection of data traffic is not common. Nevertheless, if enhanced security is deemed necessary for any reason, IPsec-based access control can be enabled on DSL networks as well by using the method described in [I-D.ietf-pana-ipsec]. 6.5. Example of Basic Flows The following flows are provided for illustration. In the proposed use case, PANA clients are implemented in hosts connected to a DSL Modem/RG acting as an Ethernet bridge (which is therefore transparent at the IP layer). IP addresses are configured using DHCP. DSL network operator allocates temporary IP addresses (e.g. private IPv4 addresses) until hosts are authenticated. After a successful authentication, hosts have to configure a new IP address for communication with other nodes. Morand, et al. Expires March 18, 2007 [Page 11] Internet-Draft PANA over DSL networks September 2006 Host BRAS DHCP Auth. Acct. (PaC) (PAA/EP) Server Server Server | | | | | | 1.DHCP Discover | | | |------------->|2.DHCP Discover| | | | |-------------->| | | | |3.DHCP Offer (PRPA) | | | |<--------------| | | |4.DHCP Offer(PRPA) | | | |<-------------| | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-++-+-+-+-+-+-+-+-+-+ | | PANA Authentication Phase | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-++-+-+-+-+-+-+-+-+-+ | | 5.DHCP Discover | | | |------------->| 6.DHCP Discover | | | |-------------->| | | | | 7.DHCP Offer (POPA) | | | |<--------------| | | | 7.DHCP Offer(POPA) | | | |<-------------| | | | +-+-+-+-+-+-+-+-+-+-+ | | | | PaC Updating | | | | | IP Address | | | | +-+-+-+-+-+-+-+-+-+-+ | | | | | 8. ACR(START) | | | |------------------------------------------->| | | 9. ACA | | | |<-------------------------------------------| | | | | | | | | | | | | | | | Disconnection | | | | =================X | | | | | 10. ACR(STOP) | | | |------------------------------------------->| | | 11. ACA | | | |<-------------------------------------------| | | | | | Figure 5: Basic Flows The host performs a DHCP procedure to configure an IP address that will be used as PRPA. After configuration of the IP address, a PANA authentication procedure is performed between the host and the BRAS, that involves here a remote authentication server . This phase may be initiated either by the host or the BRAS detecting the use of the Morand, et al. Expires March 18, 2007 [Page 12] Internet-Draft PANA over DSL networks September 2006 PRPA. For further details, see [I-D.ietf-pana-pana]. Following a successful authentication/authorization, the Authentication server passes any relevant service parameters for this subscriber IP session. The BRAS authorizes therefore the creation of the PANA session and creates an IP Session context for that subscriber. The user service policy is applied to the IP session. As a temporary IP address was used as PRPA, the host performs a new DHCP procedure to configure a permanent IP address (aka POPA). When configured, the PaC notifies the PAA about the change of address and the BRAS updates the IP Session context with this new IP address. For further details, see [I-D.ietf-pana-pana]. The BRAS should start accounting at this stage (using for instance Accounting Request (ACR) START and Accounting Answer (ACA) over a Diameter interface with a remote accounting server). When the user disconnects (L2 indication) or if there is an explicit PANA session termination request, the IP Session is terminated and accounting of the IP Session is stopped. 7. Security Considerations The DSL infrastructure that connects the CPE to the DSLAM/BRAS is assumed to run over a physically-secured non-shared media. For that reason, neither the use of a key-generating EAP method nor a secure L2/L3 channel bootstrapped by PANA is required. The current DSL deployments are satisfied by using non-key-generating client-only authentication methods (e.g., CHAP and its EAP equivalent EAP-MD5). The same model can be maintained even with the PANA-based deployments. If next generation deployments prefer key-generating mutual authentication methods, they can be naturally used with PANA too. 8. References 8.1. Normative References [I-D.ietf-dhc-paa-option] Kumar, S., "DHCP options for PANA Authentication Agents", draft-ietf-dhc-paa-option-04 (work in progress), September 2006. Morand, et al. Expires March 18, 2007 [Page 13] Internet-Draft PANA over DSL networks September 2006 [I-D.ietf-pana-pana] Forsberg, D., "Protocol for Carrying Authentication for Network Access (PANA)", draft-ietf-pana-pana-12 (work in progress), August 2006. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC 2131, March 1997. [RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., and M. Carney, "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", RFC 3315, July 2003. [RFC3748] Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J., and H. Levkowetz, "Extensible Authentication Protocol (EAP)", RFC 3748, June 2004. 8.2. Informative References [I-D.ietf-pana-framework] Jayaraman, P., "Protocol for Carrying Authentication for Network Access (PANA) Framework", draft-ietf-pana-framework-07 (work in progress), August 2006. [I-D.ietf-pana-ipsec] Parthasarathy, M., "PANA Enabling IPsec based Access Control", draft-ietf-pana-ipsec-07 (work in progress), July 2005. [I-D.ietf-pana-snmp] Mghazli, Y., "SNMP usage for PAA-EP interface", draft-ietf-pana-snmp-06 (work in progress), June 2006. [RFC2461] Narten, T., Nordmark, E., and W. Simpson, "Neighbor Discovery for IP Version 6 (IPv6)", RFC 2461, December 1998. [RFC3927] Cheshire, S., Aboba, B., and E. Guttman, "Dynamic Configuration of IPv4 Link-Local Addresses", RFC 3927, May 2005. [RFC4058] Yegin, A., Ohba, Y., Penno, R., Tsirtsis, G., and C. Wang, "Protocol for Carrying Authentication for Network Access (PANA) Requirements", RFC 4058, May 2005. Morand, et al. Expires March 18, 2007 [Page 14] Internet-Draft PANA over DSL networks September 2006 [TR25] DSL Forum TR-025, "Core Network Architecture for Access to Legacy Data Network over ADSL", September 1999. [TR59] DSL Forum TR-059, "DSL Evolution - Architecture Requirements for the Support of QoS-Enabled IP Services", September 2003. [WT134] DSL Forum WT-134 Draft Version 1.0, "Policy Control Framework for DSL", April 2006. [WT146] DSL Forum WT-146 Draft Version 1.0, "IP Sessions", February 2006. Authors' Addresses Lionel Morand France Telecom R&D 38-40 rue du general Leclerc 92794 Issy-Les-Moulineaux Cedex 9 France Phone: +33 1 45296257 Email: lionel.morand@orange-ft.com Roberta Maglione Telecom Italia Via G. Reiss Romoli 274 10148 Torino, Italy Email: mario.ullio@telecomitalia.it John Kaippallimalil Huawei Technologies 1700 Alma Drive, Suite 100 Plano, TX, USA Phone: +1 972 509 5599 Email: jkaippal@huawei.com Morand, et al. Expires March 18, 2007 [Page 15] Internet-Draft PANA over DSL networks September 2006 Alper E. Yegin Samsung Email: alper01.yegin@partner.samsung.com Morand, et al. Expires March 18, 2007 [Page 16] Internet-Draft PANA over DSL networks September 2006 Full Copyright Statement Copyright (C) The Internet Society (2006). 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. 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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). Morand, et al. Expires March 18, 2007 [Page 17]