Network Working Group M. Bocci Internet Draft A. Zinin M. Aissaoui D. Papadimitriou A. Dolganow Alcatel Yuji Kamite NTT Communications Expires: June 2007 December 7, 2006 OSPF Extensions for Dynamic Multi-segment Pseudo Wires draft-dolganow-pwe3-ospf-ms-pw-ext-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. Funding for the RFC Editor function is currently provided by the Internet Society. This document may only be posted in an Internet-Draft. 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 June 7, 2007. Abstract Dolganow et. al. Expires June 7, 2007 [Page 1] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 Multi-segment pseudo wires have been defined to enable emulated layer 1 and layer 2 services to be delivered from an IP based packet switched network over a sparse mesh of PSN tunnels and PW control protocol adjacencies. MS-PWs can be used to scale PW based networks over both a single AS, or between multiple ASs. However, there is a particular need to be able to automatically route MS-PWs through access and metro PSNs. These networks typically comprise a single AS. This draft proposes extensions to OSPF to enable the automatic advertisement of summarized PW FECs, thus enabling the automatic routing of MS-PWs across an OSPF domain. Conventions used in this document In examples, "C:" and "S:" indicate lines sent by the client and server respectively. 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 [1]. Table of Contents 1. Introduction...............................................34 1.1. Terminology...........................................45 1.2. Architecture..........................................45 2. Applicability..............................................57 3. OSPF Extensions............................................67 3.1. Attachment Circuit Addressing..........................67 3.2. S-PE Addressing........................................68 3.3. OSPFv2 LSAs...........................................68 3.3.1. Pseudo Wire Switching LSA.........................68 3.4. OSPFv3 LSAs...........................................89 3.4.1. Pseudo Wire Switching LSA.........................89 3.5. LSA Information Field.................................810 3.5.1. AII TLV.........................................911 3.5.2. PW Adjacency TLV.................................911 4. Procedures for Advertising PW Signaling Adjacencies........1011 5. LSA Processing Procedures.................................1012 5.1. P Routers...........................................1112 5.2. PE Routers..........................................1112 Deployment Considerations....................................1113 6.1. Impact on Existing P-Routers.........................1113 6.2. Congestion in the Underlying PSN Routing.............1213 7. Security Considerations...................................1214 8. IANA Considerations......................................1214 Dolganow et. al. Expires June 7, 2007 [Page 2] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 9. Acknowledgments..........................................1214 10. References..............................................1315 10.1. Normative References................................1315 10.2. Informative References..............................1315 Author's Addresses..........................................1416 Intellectual Property Statement..............................1516 Disclaimer of Validity......................................1516 Copyright Statement.........................................1517 Acknowledgment..............................................1517 1. Introduction Multi-segment pseudo wires have been defined to enable emulated layer 2 services to be delivered from an IP based packet switched network over a sparse mesh of PSN tunnels and PW control protocol adjacencies. MS-PWs can be used to scale PW based networks over both a single AS, or between multiple ASs. Requirements for MS-PWs are detailed in [8]. A basic approach to MS-PWs, where the switching points are statically placed, is described in [10]. This is extended in [11] to allow the automatic placement of the MS-PWs. This draft uses FEC 129 with AII type II to summarize the PW end points that are reachable through a given PE, and to provide a layer 2 address for the S-PEs. MP-BGP is used to distribute FECs. However, although MP-BGP may be used within a single AS, the use of MP-BGP is primarily focused on scenarios where each PWE3 domain is a separate AS, and S-PEs are used to switch PWs between adjacent ASs. A second important case is where MS-PWs are deployed in service provider access and metro networks. Pseudo wires in these networks typically span only a single IGP domain or AS. Furthermore, the nodes contain a minimal routing implementation to cut operational complexity. MP-BGP is not typically deployed on MTUs and full MP-BGP functionality may not be required. However, there is also a particular need to be able to automatically route MS-PWs through these topologies. These two cases demonstrate the need for a MS-PW routing protocol for: - MP-BGP incapable domains. - Domains where only an incremental increase in routing functionality is required over the simple statically placed MS- PWs. Dolganow et. al. Expires June 7, 2007 [Page 3] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 In these cases, it is possible to leverage the mechanisms of the PSN IGP to distribute MS-PW routing information. This draft proposes extensions to OSPF to enable the automatic advertisement of summarized PW layer 2 addresses within a single AS, thus enabling the automatic routing of MS-PWs across an OSPF domain. This information is then used by T-PEs and S-PEs to derive the MS-PW routing tables. These are used to signal the next-hop S-PE or T-PE, as described in [11]. 1.1. Terminology The terminology defined in [9] applies. 1.2. Architecture +----+ +----+ |TPE1+--------------------------------------------------+TPE2| +----+ +----+ |<---------------------------PW----------------------------->| +----+ +---+ +---+ +----+ |TPE1+--------------+SPE+-----------+SPE+---------------+TPE2| +----+ +---+ +---+ +----+ <---------------------- Single AS --------------------------> Figure 1 MS-PW Routing Model Figure 1Figure 1 illustrates the MS-PW routing model. ACs attached to TPE2 are associated with the OSPF Router_ID or any locally assigned routable address. The proposed model assumes the existence of a signaling adjacency between T-PE/S-PE, S-PE/S-PE and/or S-PE/T-PE. An example of a signaling adjacency is a Targeted LDP session used by MS-PW signaling [11]. A pair of routable IP addresses represents this signaling adjacency. Each S-PE / T-PE is also assigned its own layer 2 address in the form of an AII as described in [11] Dolganow et. al. Expires June 7, 2007 [Page 4] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 When such an adjacency is to be used for the establishment of intermediate PW segments, both ends can advertise the set of AIIs reachable across this set of intermediate PW segments. This is done using summarized Type 2 AIIs so that a separate advertisement is not required to every AC reachable via that adjacency. AIIs may be summarized using the aggregation rules for AII Type 2 described in [6]. The corresponding advertisement is modeled a set of PE nodes, interconnected with signaling adjacencies, and a set of AII's associated with each node. The resulting topology is a connected graph that identifies each S-PE by an AII (which includes its IP address), an optional set of PW links between PEs, and each T-PE by one or more AIIs containing an IP address for the T-PE and a set of AC identifiers. Based on that topology, each PE builds a routing information containing all routable AIIs. When creating MS-PW, the PE looks up the AII and determines the next hop PE for LDP signalling as described in [11]. Figure 1Figure 1 depicts the simple model of one-to-one relations of a T-PE to S-PE and S-PE to S-PE, and of a single S-PE to S-PE segment. In the general case, multiple S-PE segments will exist, and the relation between two S-PEs or/and T-PE and S-PEs will be one-to- many or many-to-one. Processing in these cases follows that of the general case illustrated in Figure 1Figure 1. Selection of an S-PE from a set of multiple available S-PEs is left for further revisions of this draft. 2. Applicability The proposed OSPF protocol extensions are intended for domains where MP-BGP is not used. In many cases, this will apply to routing MS-PWs across a single AS, where the source T-PE (ST-PE), the Terminating T- PE (TT-PE) and all of the intermediate S-PEs reside in the same AS. However, the above application does not preclude cases where OSPF is used to route one portion of a MS-PW across a given AS where the ST- PE and the TT-PE reside in different ASs. Here, OSPF is used to advertise the AIIs reachable through S-PEs corresponding to ASBRs. This enables the ingress S-PEs and intermediate S-PEs in an AS to route MS-PWs to the correct egress S-PE in the AS to reach a TT-PE in another AS. This draft does not define how the egress S-PE learns what AIIs are externally reachable through it, but this could be by configuration, or by an exterior gateway protocol. Dolganow et. al. Expires June 7, 2007 [Page 5] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 3. OSPF Extensions 3.1. Attachment Circuit Addressing As in [11], attachment circuit addressing is derived from AII type 2 [2], as shown in the following figure: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | AII Type=02 | Length | Global ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Global ID (contd.) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Prefix | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | AC ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1 Attachment Circuit Addressing Implementations of this procedure MUST interpret the AII as described in [11]. 3.2. S-PE Addressing The T-PE may select a known specific path along a set of S-PEs for a specific PW. This requires that each S-PE be uniquely addressable in terms of pseudo wires. For this purpose at least one AII address of the format similar to AII type 2 composed of the Global ID, and Prefix part only MUST be assigned to each S-PE. The prefix must be derived from the S-PE address associated to the locally assigned routable address. 3.3. OSPFv2 LSAs This extension makes use of the opaque LSA. One new LSA is defined: the PW Switching LSA This LSA describes the S-PEs/T-PEs, and PSN tunnels between peer S-PEs or T-PEs. 3.3.1. Pseudo Wire Switching LSA OSPFv2 routers behaving as S-PEs or T-PEs MAY optionally advertise the layer 2 addresses reachable through them. This advertisement MUST be in an AS-scoped opaque LSA. Dolganow et. al. Expires June 7, 2007 [Page 6] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 The format of the OSPFv2 opaque LSA is as follows: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | LS age | Options | Scope | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Opaque Type | Opaque ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Advertising Router | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | LS Sequence Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | LS checksum | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | LSA Information | + + | ... | Options Field: The options field is described in RFC2370 [3]. The 'O' bit MUST be set to 1. The values of the other bits are TBD. Scope: This is set to the topological flooding scope of the LSA. Normally this is type 11 (AS-wide). Opaque type: This field identifies the LSA to be of type PW Switching. Its value is TBD. Opaque ID: This is set to TBD Advertising Router: The OSPF router ID of the originating router. LSA Information: This is formatted as described in Section 3.5. below. Dolganow et. al. Expires June 7, 2007 [Page 7] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 3.4. OSPFv3 LSAs 3.4.1. Pseudo Wire Switching LSA The OSPFv3 PW switching LSA has a function code of TBD. The S1/S2 bit are set to indicate an AS flooding scope for the LSA. The U bit is set indicating the OSPFv3 PW switching LSA should be flooded even if it is not understood. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | LS age |1|S12| 12 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Link State ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Advertising Router | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | LS sequence number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | LS checksum | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | +- LSA Information -+ | ... | LSA Information: This is formatted as described in Section 3.5. below. 3.5. LSA Information Field The LSA information consists of two or more nested Type/Length/Value (TLV) triplets. The format of each TLV is: Dolganow et. al. Expires June 7, 2007 [Page 8] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Value... | . . . . . . +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The LSA MUST contain a TLV for the IP address of the advertising router. For OSPF v2 routers, this is the Router Address TLV defined in Section 2.4.1 of RFC 3630 [4]. For OSPF v3 routers, this is the Router IPv6 Address TLV specified in Section 3 of draft-ietf-ospf- ospfv3-traffic-07.txt [5]. In each of these, the router address MUST be set to the IP address of the advertising T-PE/S-PE. This document defines two additional TLVs: : Type TBD: AII Type TBD: PW Adjacency 3.5.1. AII TLV If the LSA information is of type AII, then the value field contains one or more AII Type 2 TLVs, as described above. 3.5.2. PW Adjacency TLV The PW Adjacency TLV is used to describe the presence of a PW signaling adjacency between two S-PEs or T-PEs. The PW Adjacency TLV contains the following sub TLVs: o Advertising PE Layer 2 Address: This is the AII Type 2 address of the local PE o Remote PE Layer 2 Address: This is the AII Type 2 address of the remote PE at the far end of the PW signaling session Extensions to the PW Adjacency TLV to support the advertisement of traffic engineering information and other metrics are for further study. Dolganow et. al. Expires June 7, 2007 [Page 9] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 4. Procedures for Advertising PW Signaling Adjacencies The signaling adjacencies that exist between S-PEs and T-PEs must be advertised. However, the PWE3 topology over which PWs can be signaled is a superset of the MS-PW topology, and it is assumed that the PWE3 topology coincides with the topology of PWE3 control protocol (i.e. PW signaling) adjacencies. That is, not all PEs can be S-PEs, and not all S-PEs can be assumed to be capable of dynamic PW routing. In order to use a given signaling session to a peer S-PE/T-PE to signal dynamically placed MS-PWs, S-PEs/T-PEs need to know which of the PW adjacency TLVs received represent switching capable PEs along a path to reach advertised AIIs. The following procedure is used to establish this association. T-PEs/S-PEs that are switching capable announce this using the PW adjacency TLV in the PW switching LSA. The PW adjacency TLV contains all of the configured adjacencies currently operationally up. A T- PE/S-PE must associate the originator of that LSA with the endpoint of one of its own signaling sessions (either directly or through another PW adjacency TLV in case of multi-hop switching) In a single hop case, this may be achieved automatically by matching router IP addresses in the LSA with signaling endpoints, or by configuration. 5. LSA Processing Procedures Nodes capable of pseudowire switching on either side of a signaling session exchange PW switching LSAs with the AII and PW adjacency TLV. Note that the PW adjacency TLV will only contain those adjacencies that are currently configured and operationally up (i.e. targeted LDP session is operationally UP ). These PW switching LSAs are processed and flooded as described in Section 5.2. The signaling adjacency is maintained using a signaling protocol specific mechanism e.g. LDP hellos. Changes in the state of the adjacency should be advertised using the updated PW adjacency TLV within the PW switching LSA. A router should use a mechanism to reduce the number of advertisements in case of bouncing signalling adjacency. Such a mechanism is out of scope for this specification. The application database includes thus a set of signaling sessions (PW signaling adjacencies) that may be used for signaling dynamically placed MS-PWs. AII TLV associates end-point information to the PW adjacency (that are providing access to these end-points). AII TLVs are flooded in the PW switching opaque LSA. Dolganow et. al. Expires June 7, 2007 [Page 10] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 5.1. P Routers OSPF routers that receive LSAs described in this document and that are not S-PEs or T-PEs MUST flood them according to the rules of OSPFv2 or OSPFv3, as applicable. 5.2. PE Routers S-PEs and T-PEs that are OSPF routers and that receive LSAs described in this document MUST flood them according to the rules of OSPFv2 or OSPFv3, as applicable. These LSAs are also installed in a PW link state database. The link state database, which represents a connected graph of S-PEs and T-PEs (as described above) MAY be used by S-PEs and T-PEs to calculate a PW routing table. The PW routing table has the structure described in Section 7 of [11], and is used to determine the next signaling hop when a S-PE receives a PW setup message as described in that draft. PW static routes may also be provisioned, as described in [11]. The algorithm used to calculate the PW routing table from the link state database, and the application of routing constraints, is beyond the scope of this draft. However, all T-PEs and S-PEs within the same PWE3 domain SHOULD use the same algorithm. 6. Deployment Considerations Addition and Removal of ACs, S-PEs and T-PEs The operational and deployment considerations for the addition and removal of S-PEs, T-PEs and ACs will be described in a future version of this draft. 6.1. Impact on Existing P-Routers P-routers supporting Opaque LSA processing procedures must exist along the flooding path in the AS to ensure propagation of the information required for dynamic pseudowire routing. Ideally, multiple "Opaque LSA" flooding paths exist, so a failure of a router along a path does isolate subset of a network. Routers supporting Opaque LSA processing as described in [3], will flood the LSAs as specified in [3]. The impact of this additional flooding load may be constrained through appropriate levels of Dolganow et. al. Expires June 7, 2007 [Page 11] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 aggregation of AIIs. Section 6.2. below describes other methods for limiting the impact of any additional flooding. 6.2. Congestion in the Underlying PSN Routing This document describes the use of the underlying interior gateway protocol in an IP network to advertise routing information for the automatic placement of MS-PWs. Congestion may occur in the routing plane of the PSN if a large amount of pseudowire LSAs are flooded. It is therefore important to ensure that this does not degrade the performance of the IGP for the underlying PSN. Implementations may use a number of methods to avoid routing congestion, including: o Separate IGP instances for the underlying PSN and for the MS-PWs. o Prioritization of PSN LSAs over PW Switching LSAs. o Rate limiting PW Switching LSAs so that they do not consume excessive bandwidth or route processor capacity. o OSPF Refresh and Flooding reduction mechanisms as defined in [7]. 7. Security Considerations This section will be added in a future version. 8. IANA Considerations This document requests that the following allocations be made from existing registries: o The OSPFv2 opaque LSA type TBD for the PW switching opaque LSA. o The OSPFv3 LSA type function code TBD for the PW switching LSA 9. Acknowledgments The authors gratefully acknowledge the contributions of Vach Kompella, Devendra Raut and Yuichi Ikejiri. Dolganow et. al. Expires June 7, 2007 [Page 12] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 10. References 10.1. Normative References [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [2] Metz, C., et al, "AII Types for Aggregation", Internet Draft, draft-metz-aii-aggregate-01.txt, October 2006. [3] Coltun, R., " The OSPF Opaque LSA Option", RFC 2370, July 1998 [4] Katz D. et al., "Traffic Engineering (TE) Extensions to OSPF Version 2", RFC 3630, September 2003 [5] Ishiguro K. et al., "Traffic Engineering Extensions to OSPF version 3", Internet Draft, draft-ietf-ospf-ospfv3-traffic- 07.txt, April 2006 [6] Metz C. et al., "Pseudowire Attachment Identifiers for Aggregation and VPN Autodiscovery", Internet Draft, draft-ietf- pwe3-aii-aggregate-01.txt, October 2006 [7] Pillay-Esnault P., "OSPF Refresh and Flooding Reduction in Stable Topologies", RFC 4136, July 2005 10.2. Informative References [8] Bitar, N., Bocci, M., and Martini, L., "Requirements for inter domain Pseudo-Wires", Internet Draft, draft-ietf-pwe3-ms-pw- requirements-02.txt, May 2006 [9] Bocci, M., and Bryant, S.,T., " An Architecture for Multi- Segment Pseudo Wire Emulation Edge-to-Edge", Internet Draft, draft-ietf-pwe3-ms-pw-arch-01.txt, May 2006 [10] Martini et al, "Segmented Pseudo Wire", Internet Draft, draft- ietf-pwe3-segmented-pw-02.txt, March 2006 [11] Martini, L., Bocci, M., Balus, F., et al, " Dynamic Placement of Multi Segment Pseudo Wires", Internet Draft, draft-ietf- pwe3-dynamic-ms-pw-00.txt, December 2005 Dolganow et. al. Expires June 7, 2007 [Page 13] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 Author's Addresses Matthew Bocci Alcatel-Lucent Voyager Place, Shoppenhangers Road Maidenhead Berks, UK Email: matthew.bocci@alcatel-lucent.co.uk Dimitri Papadimitriou Alcatel-Lucent Copernicuslaan 50 2018 ANTWERP BELGIUM Email: dimitri.papadimitriou@alcatel-lucent.be Alex Zinin ALCATEL-Lucent. 701 East Middlefield Road M/S MOUNT-HRPB6 MOUNTAIN VIEW, CA 94043 USA Email: alex.zinin@alcatel-lucent.com Mustapha Aissaoui Alcatel-Lucent 600 March Road OTTAWA, ON K2K 2E6 CANADA Email: mustapha.aissaoui@alcatel-lucent.com Andrew Dolganow Alcatel-Lucent 600 March Road OTTAWA, ON K2K 2E6 CANADA Email: andrew.dolganow@alcatel-lucent.com Yuji Kamite NTT Communcations Email: y.kamite@ntt.com Dolganow et. al. Expires June 7, 2007 [Page 14] Internet-Draft OSPF Extensions for Dynamic MS-PWs December 2006 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 (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. Acknowledgment Dolganow et. al. Expires June 7, 2007 [Page 15]