Network Working Group K. Chowdhury Internet-Draft Starent Networks Expires: April 24, 2006 A. Lior Bridgewater Systems H. Tschofenig Siemens October 21, 2005 RADIUS Mobile IPv6 Support draft-chowdhury-mip6-radius-00.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 April 24, 2006. Copyright Notice Copyright (C) The Internet Society (2005). Abstract A Mobile IPv6 node requires a home agent address, a home address, and IPsec security association with its home agent before it can start utilizing Mobile IPv6 service. RFC 3775 requires that some or all of these parameters are statically configured. Ongoing work aims to make this information dynamically available to the mobile node. An Chowdhury, et al. Expires April 24, 2006 [Page 1] Internet-Draft October 2005 important aspect of the Mobile IPv6 bootstrapping solution is to support interworking with existing authentication, authorization and accounting infrastructure. This document defines the new attributes to facilitate Mobile IPv6 bootstrapping via a RADIUS infrastructure. This information exchange may take place as part of the initial network access authentication procedure or as part of a separate protocol exchange between the mobile node, the home agent and the AAA infrastructure. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Solution Overview . . . . . . . . . . . . . . . . . . . . . 5 3.1 Integrated Scenario . . . . . . . . . . . . . . . . . . . 5 3.2 Split Scenario . . . . . . . . . . . . . . . . . . . . . . 6 4. RADIUS Attribute Overview . . . . . . . . . . . . . . . . . 8 4.1 Home Agent Address Attribute . . . . . . . . . . . . . . . 8 4.2 Home Agent FQDN Attribute . . . . . . . . . . . . . . . . 8 4.3 Home Link Prefix Attribute . . . . . . . . . . . . . . . . 8 4.4 Home Address Attribute . . . . . . . . . . . . . . . . . . 8 4.5 DNS Update Mobility Option Attribute . . . . . . . . . . . 8 5. RADIUS attributes . . . . . . . . . . . . . . . . . . . . . 9 5.1 Home Agent Address Attribute . . . . . . . . . . . . . . . 9 5.2 Home Agent FQDN Attribute . . . . . . . . . . . . . . . . 10 5.3 Home Link Prefix Attribute . . . . . . . . . . . . . . . . 10 5.4 Home Address Attribute . . . . . . . . . . . . . . . . . . 11 5.5 DNS Update Mobility Option Attribute . . . . . . . . . . . 12 6. Message Flows . . . . . . . . . . . . . . . . . . . . . . . 14 7. Mapping of the Requirements . . . . . . . . . . . . . . . . 15 8. Table of Attributes . . . . . . . . . . . . . . . . . . . . 16 9. Security Considerations . . . . . . . . . . . . . . . . . . 17 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . 18 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 19 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 20 12.1 Normative References . . . . . . . . . . . . . . . . . . 20 12.2 Informative References . . . . . . . . . . . . . . . . . 20 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 21 Intellectual Property and Copyright Statements . . . . . . . 22 Chowdhury, et al. Expires April 24, 2006 [Page 2] Internet-Draft October 2005 1. Introduction Mobile IPv6 specification [RFC3775] requires a Mobile Node (MN) to perform registration with a Home Agent with information about its current point of attachment (Care-of Address). The Home Agent creates and maintains binding between the MN's Home Address and the MN's Care-of Address. In order to register with a Home Agent, the MN needs to know some information such as, the Home Link prefix, the Home Agent Address, the Home Address, the Home Link prefix Length and security related information in order to secure the Binding Update. The aforementioned set of information may be statically provisioned in the MN. However, static provisioning of this information has its drawbacks. It increases provisioning and network maintenance burden for the operator. Moreover, static provisioning does not allow load balancing, failover, opportunistic home link assignment etc. For example, the user may be accessing the network from a location that may be geographically far away from the preconfigured home link; the administrative burden to configure the MN's with the respective addresses is large and the ability to react on environmental changes is minimal. In these situations static provisioning may not be desirable. Dynamic assignment of Mobile IPv6 home registration information is a desirable feature for ease of deployment and network maintenance. For this purpose, the RADIUS infrastructure, which is used for access authentication, can be leveraged to assign some or all of the necessary parameters. The RADIUS server in the Access Service Provider (ASP) or in the Mobility Service Provider's (MSP) network may return these parameters to the AAA client. The AAA client might either be the NAS, in case of the integrated scenario, or the home agent, in case of the split scenario. The terms integrated and split are described in the terminology section and were introduced in [BOOT-PS]. Chowdhury, et al. Expires April 24, 2006 [Page 3] Internet-Draft October 2005 2. Terminology The keywords "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]. General mobility terminology can be found in [RFC3753]. The following additional terms, as defined in [BOOT-PS], are used in this document: Access Service Authorizer (ASA): A network operator that authenticates a mobile node and establishes the mobile node's authorization to receive Internet service. Access Service Provider (ASP): A network operator that provides direct IP packet forwarding to and from the mobile node. Mobility Service Authorizer (MSA): A service provider that authorizes Mobile IPv6 service. Mobility Service Provider (MSP): A service provider that provides Mobile IPv6 service. In order to obtain such service, the mobile node must be authenticated and authorized to obtain the Mobile IPv6 service. Split scenario: A scenario where the mobility service and the network access service are authorized by different entities. Integrated Scenario: A scenario where the mobility service and the network access service are authorized by the same entity. Chowdhury, et al. Expires April 24, 2006 [Page 4] Internet-Draft October 2005 3. Solution Overview This document addresses the authentication, authorization and accounting functionality required by for the MIPv6 bootstrapping as outlined in the MIPv6 bootstrapping problem statement document (see [BOOT-PS]). As such, the AAA functionality for the integrated and the split scenario needs to be defined. This requires the ability to offer support for the home agent to AAA server and the network access server to AAA server communication. To highlight the main use cases, we briefly describe the integrated and the split scenarios in Section 3.1 and Section 3.2, respectively. 3.1 Integrated Scenario In the integrated scenario MIPv6 bootstrapping is provided as part of the network access authentication procedure. Figure 1 shows the participating entity. +---------------------------+ +-----------------+ |Access Service Provider | |ASA/MSA/(/MSP) | |(Mobility Service Provider)| | | | | | +-------+ | | +-------+ | | |Remote | | | |Local | RADIUS | | |RADIUS | | | |RADIUS |-------------------------|Server | | | |Proxy | | | +-------+ | | +-------+ | | ^ | | ^ | | |RADIUS | | | | | | | | | | | v | | |RADIUS | | +-------+ | | | +-------+ | | |Local | | | | RADIUS |Home | | | |Home | | | | +----->|Agent | | | |Agent | | | | | |in ASP | | | +-------+ | | v v +-------+ | +-----------------+ +-------+ IEEE | +-----------+ +-------+ | |Mobile | 802.1X | |NAS / Relay| |DHCPv6 | | |Node |----------+-|RADIUS |---|Server | | | | PANA,... | |Client | | | | +-------+ DHCP | +-----------+ +-------+ | +---------------------------+ Figure 1. Mobile IPv6 service access in the integrated scenario Chowdhury, et al. Expires April 24, 2006 [Page 5] Internet-Draft October 2005 In the typical Mobile IPv6 access scenario as shown above, the MN attaches in a Access Service Provider's network. During this network attachment procedure, the NAS/RADIUS client interacts with the mobile node. As shown in Figure 1, the authentication and authorization happens via a RADIUS infrastructure. At the time of authorizing the user for IPv6 access, the RADIUS server in the MSA detects that the user is authorized for Mobile IPv6 access. Based on the MSA's policy, the RADIUS server may allocate several parameters to the MN for use during the subsequent Mobile IPv6 protocol interaction with the home agent. Depending on the details of the solution interaction with the DHCPv6 server may be required, as described in [DHCP-INT]. 3.2 Split Scenario In the split scenario, Mobile IPv6 bootstrapping is not provided as part of the network access authentication procedure. The Mobile IPv6 bootstrapping procedure is executed with the Mobility Service Provider when desired by the mobile node. Two variations can be considered: a) the MSA and the MSP are the same entity. b) the MSA and the MSP are different entities. Since scenario (b) is the more generic scenario we show it in Figure 2. Chowdhury, et al. Expires April 24, 2006 [Page 6] Internet-Draft October 2005 +----------------------+ | | |Mobility +-------+ | |Service |Remote | | |Authorizer |RADIUS | | |(MSA) |Server | | | +-------+ | +---------------^------+ | |RADIUS | | +---------------------------------|------+ |Mobility Service Provider (MSP) v | +-------+ | +-----------+ +-------+ | |Mobile | MIPv6 / | |Home Agent/| RADIUS |Local | | |Node |-------------|RADIUS |-------------- |RADIUS | | | | IKEv2 | |Client | |Proxy | | +-------+ | +-----------+ +-------+ | +----------------------------------------+ Figure 2. Mobile IPv6 service access in the split scenario (MAS != MSP) As shown in Fig. 2 the interaction between the RADIUS client and the RADIUS server is triggered by the protocol interaction between the mobile node and the home agent/RADIUS client using IKEv2 (see [BOOT- SPLIT]). The home agent / RADIUS Client interacts with the RADIUS infrastructure to perform authentication, authorization, accounting and parameter bootstrapping. The exchange is triggered by the home agent and an interaction with the RADIUS infrastructure is initiated. When the protocol exchange is completed then the home agent needs to possess the Mobile IPv6 specific parameters (see [BOOT-PS]). Additionally, the mobile node might instruct the RADIUS server (via the home agent) to perform a dynamic DNS update. Chowdhury, et al. Expires April 24, 2006 [Page 7] Internet-Draft October 2005 4. RADIUS Attribute Overview 4.1 Home Agent Address Attribute The RADIUs server may decide to assign a Home Agent to the MN that is in close proximity to the point of attachment (e.g., determined by the NAS-ID). There may be other reasons for dynamically assigning Home Agents to the MN, for example to share the traffic load. The attribute also contains the prefix length so that the MN can easily infer the Home Link prefix from the Home Agent address. 4.2 Home Agent FQDN Attribute The RADIUS server may assign an FQDN of the home address to the MN. The mobile node can perform DNS query with the FQDN to derive the home agent address. 4.3 Home Link Prefix Attribute For the same reason as the HA assignment, the RADIUS server may assign a Home Link that is in close proximity to the point of attachment (NAS-ID). The MN can perform [RFC3775] specific procedures to discover other information for Mobile IPv6 registration. 4.4 Home Address Attribute The RADIUS server may assign a Home Address to the MN. This allows the network operator to support mobile devices that are not configured with static addresses. The attribute also contains the prefix length so that the MN can easily infer the Home Link prefix from the Home Agent address. 4.5 DNS Update Mobility Option Attribute By using this payload the RADIUS client instructs the RADIUS server to perform a dynamic DNS update. When this payload is included in the reverse direction, i.e., from the RADIUS server to the RADIUS client, it informs about the status of the dynamic DNS update. When the payload is sent from the RADIUS client to the RADIUS server then the response MUST include the DNS Update Mobility Option attribute. Chowdhury, et al. Expires April 24, 2006 [Page 8] Internet-Draft October 2005 5. RADIUS attributes This section defines format and syntax for the attribute that carries the Mobile IPv6 parameters that are described in the previous section. The attributes MAY be present in Access-Accept, Accounting-Request. 5.1 Home Agent Address Attribute This attribute is sent by the RADIUS server to the NAS in an Access- Accept message. The attribute carries the assigned Home Agent address. 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 | Reserved | Prefix-Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | | | IPv6 address of assigned Home Agent | | | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type: ASSIGNED-HA-ADDR-TYPE to be defined by IANA. Length: = 20 octets Reserved: Reserved for future use. All bits set to 0. Prefix-Length: This field indicates the prefix length of the Home Link. IPv6 address of assigned Home Agent: Chowdhury, et al. Expires April 24, 2006 [Page 9] Internet-Draft October 2005 128-bit IPv6 address of the assigned Home Agent. 5.2 Home Agent FQDN Attribute This attribute is sent by the RADIUS server to the NAS in an Access- Accept message. The attribute carries the FQDN of the assigned home agent. 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 | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | FQDN of the assigned home agent ... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type: ASSIGNED-HA-FQDN-TYPE to be defined by IANA. Length: Variable length. Reserved: Reserved for future use. All bits set to 0. FQDN of the assigned home agent: The data field MUST contain a FQDN as described in [RFC1035]. 5.3 Home Link Prefix Attribute This attribute is sent by the RADIUS-MIP server to the NAS in an Access-Accept message. The attribute carries the assigned Home Link prefix. Chowdhury, et al. Expires April 24, 2006 [Page 10] Internet-Draft October 2005 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 | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | | | Home Link Prefix | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type: ASSIGNED-HL-TYPE to be defined by IANA. Length: >= 4 octets + the minimum length of a prefix. Reserved: Reserved for future use. All bits set to 0. Home Link Prefix: Home Link prefix (upper order bits) of the assigned Home Link where the MN should send binding update. 5.4 Home Address Attribute This attribute is sent by the RADIUS server to the NAS in an Access- Accept message. The attribute carries the assigned Home IPv6 Address for the MN. 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 | Reserved | Prefix-Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | | | Assigned IPv6 Home Address | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Chowdhury, et al. Expires April 24, 2006 [Page 11] Internet-Draft October 2005 Type: ASSIGNED-HOA-TYPE to be defined by IANA. Length: = 20 octets. Reserved: Reserved for future use. All bits set to 0. Prefix-Length: This field indicates the prefix length of the Home Link. Assigned IPv6 Home Address: IPv6 Home Address that is assigned to the MN. 5.5 DNS Update Mobility Option Attribute The DNS Update Mobility Option attribute is used for triggering a DNS update by the RADIUS server and to return the result to the RADIUS client. The request MUST carry the mobile node's FQDN but the attribute carried in response to the request MAY not carry a FQDN value. 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 | Reserved-1 | Status | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |R| Reserved-2 | FQDN ... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type: DNS-UPDATE-TYPE to be defined by IANA. Length: Chowdhury, et al. Expires April 24, 2006 [Page 12] Internet-Draft October 2005 Variable length. Reserved-1: Reserved for future use. All bits set to 0. Status: This 8 bit unsigned integer field indicates the result of the dynamic DNS update procedure. This field MUST be set to 0 and ignored by the RADIUS server when the DNS Update Mobility Option is sent from the RADIUS client to the RADIUS server. When the DNS Update Mobility Option is provided in the response, values of the Status field less than 128 indicate that the dynamic DNS update was performed successfully by the RADIUS server. Values greater than or equal to 128 indicate that the dynamic DNS update was not successfully completed. The following values for the Status field are currently defined: 0 DNS update performed 128 Reason unspecified 129 Administratively prohibited 130 DNS Update Failed R flag: If this bit for the R flag is set then the RADIUS client requests the RADIUS server to remove the DNS entry identified by the FQDN included in this attribute. If not set, the RADIUS client is requesting the RADIUS server to create or update a DNS entry with the FQDN specified in this attribute and the Home Address carried in another attribute specified in this document. Reserved-2: Reserved for future use. All bits set to 0. FQDN of the mobile node: The data field MUST contain a FQDN as described in [RFC1035]. Chowdhury, et al. Expires April 24, 2006 [Page 13] Internet-Draft October 2005 6. Message Flows [Editor's Note: A future version of this document will provide example message flows.] Chowdhury, et al. Expires April 24, 2006 [Page 14] Internet-Draft October 2005 7. Mapping of the Requirements [Editor's Note: A future version of this document will map the requirements listed in [AAA-Goals]] with the solution provided in this document.] Chowdhury, et al. Expires April 24, 2006 [Page 15] Internet-Draft October 2005 8. Table of Attributes The following table provides a guide to which attributes may be found in RADIUS message and in what number. Request Accept Reject Challenge Attribute 0-1 0-1 0 0 Home Agent Address Attribute 0-1 0-1 0 0 Home Agent FQDN Attribute 0-1 0-1 0 0 Home Link Prefix Attribute 0-1 0-1 0 0 Home Address Attribute 0-1 0-1 0 0 DNS Update Mobility Option Attribute The following table defines the meaning of the above table entries. 0 This attribute MUST NOT be present. 0-1 Zero or one instance of this attribute MAY be present. Chowdhury, et al. Expires April 24, 2006 [Page 16] Internet-Draft October 2005 9. Security Considerations Assignment of these values to a user should be based on successful authentication of the user at the NAS and/or at the home agent. The RADIUS server should only assign these values to a user who is authorized for Mobile IPv6 service (this check could be performed with the user's subscription profile in the Home Network). The NAS and the home agent to the RADIUS server transactions must be adequately secured. Otherwise there is a possibility that the user may receive fraudulent values from a rogue RADIUS server potentially hijacking the user's Mobile IPv6 session. These new attributes do not introduce additional security considerations besides the ones identified in [RFC2865]. Chowdhury, et al. Expires April 24, 2006 [Page 17] Internet-Draft October 2005 10. IANA Considerations The following RADIUS attribute Type values MUST be assigned by IANA. ASSIGNED-HA-ADDR-TYPE ASSIGNED-HA-FQDN-TYPE ASSIGNED-HL-TYPE ASSIGNED-HOA-TYPE DNS-UPDATE-TYPE Chowdhury, et al. Expires April 24, 2006 [Page 18] Internet-Draft October 2005 11. Acknowledgements We would like to thank the following individuals for their review and constructive comments during the development of this document: Mark Watson, Jayshree Bharatia of Nortel. Chowdhury, et al. Expires April 24, 2006 [Page 19] Internet-Draft October 2005 12. References 12.1 Normative References [BOOT-SPLIT] Giaretta et. al., G., "Mobile IPv6 bootstrapping in split scenario.", draft-ietf-mip6-bootstrapping-split-00.txt (work in progress), June 2005. [DHCP-INT] Chowdhury et. al., K., "MIP6-bootstrapping via DHCPv6 for the Integrated Scenario.", draft-ietf-mip6-bootstrapping-integrated-DHC-00.txt (work in progress), October 2005. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2865] Rigney, C., Willens, S., Rubens, A., and W. Simpson, "Remote Authentication Dial In User Service (RADIUS)", RFC 2865, June 2000. 12.2 Informative References [AAA-Goals] Giaretta et. al., G., "Goals for AAA-HA interface.", draft-ietf-mip6-aaa-ha-goals-00.txt (work in progress), April 2005. [BOOT-PS] Patel et. al., A., "Problem Statement for bootstrapping Mobile IPv6.", draft-ietf-mip6-bootstrap-ps-03.txt (work in progress), July 2005. [MIP6-IKEv2] Devarapalli, V., "Mobile IPv6 Operation with IKEv2 and the revised IPsec.", draft-ietf-mip6-ikev2-ipsec-03.txt (work in progress), September 2005. [RFC1035] Mockapetris, P., "Domain names - implementation and specification", STD 13, RFC 1035, November 1987. [RFC2136] Vixie, P., Thomson, S., Rekhter, Y., and J. Bound, "Dynamic Updates in the Domain Name System (DNS UPDATE)", RFC 2136, April 1997. [RFC3753] Manner, J. and M. Kojo, "Mobility Related Terminology", RFC 3753, June 2004. Chowdhury, et al. Expires April 24, 2006 [Page 20] Internet-Draft October 2005 [RFC3775] Johnson, D., Perkins, C., and J. Arkko, "Mobility Support in IPv6", RFC 3775, June 2004. [RFC3776] Arkko, J., Devarapalli, V., and F. Dupont, "Using IPsec to Protect Mobile IPv6 Signaling Between Mobile Nodes and Home Agents", RFC 3776, June 2004. [RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S. Rose, "DNS Security Introduction and Requirements", RFC 4033, March 2005. Authors' Addresses Kuntal Chowdhury Starent Networks 30 International Place Tewksbury, MA 01876 US Phone: +1 214-550-1416 Email: kchowdhury@starentnetworks.com Avi Lior Bridgewater Systems 303 Terry Fox Drive, Suite 100 Ottawa, Ontario Canada K2K 3J1 Phone: +1 613-591-6655 Email: avi@bridgewatersystems.com Hannes Tschofenig Siemens Otto-Hahn-Ring 6 Munich, Bavaria 81739 Germany Email: Hannes.Tschofenig@siemens.com Chowdhury, et al. Expires April 24, 2006 [Page 21] Internet-Draft October 2005 Intellectual Property Statement 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. Disclaimer of Validity 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 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. Copyright Statement Copyright (C) The Internet Society (2005). 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. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Chowdhury, et al. Expires April 24, 2006 [Page 22]