Network Working Group Y. Lee Internet Draft Huawei Intended status: Standard R. Casellas Expires: August 2011 CTTC February 18, 2011 PCEP Extension for WSON Routing and Wavelength Assignment draft-lee-pce-wson-rwa-ext-00.txt Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and 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." 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Abstract This draft provides the Path Computation Element communication Protocol (PCEP) extensions for the support of Routing and Wavelength Assignment (RWA) in Wavelength Switched Optical Networks (WSON). Lightpath provisioning in WSONs requires a routing and wavelength assignment (RWA) process. From a path computation perspective, wavelength assignment is the process of determining which wavelength can be used on each hop of a path and forms an additional routing constraint to optical light path computation. Conventions used in this document 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 0. Table of Contents 1. Introduction...................................................3 2. WSON PCE Architectures and Requirements........................4 2.1. Encoding of a new RWA path request........................5 2.1.1. Wavelength Range Constraint TLV......................6 2.2. Encoding of a RWA Path Reply..............................9 2.2.1. Wavelength Range Constraint TLV.....................11 2.3. Error Indicator..........................................11 2.4. NO-PATH Indicator........................................12 3. Manageability Considerations..................................12 3.1. Control of Function and Policy...........................12 3.2. Information and Data Models, e.g. MIB module.............13 3.3. Liveness Detection and Monitoring........................13 3.4. Verifying Correct Operation..............................13 3.5. Requirements on Other Protocols and Functional Components13 3.6. Impact on Network Operation..............................14 4. Security Considerations.......................................14 5. IANA Considerations...........................................14 Lee & Casellas Expires August 18, 2011 [Page 2] Internet-Draft PCEP Extension for WSON RWA February 2011 6. Acknowledgments...............................................14 7. References....................................................14 7.1. Normative References.....................................14 7.2. Informative References...................................15 Authors' Addresses...............................................16 Intellectual Property Statement..................................16 Disclaimer of Validity...........................................16 1. Introduction [RFC4655] defines the PCE based Architecture and explains how a Path Computation Element (PCE) may compute Label Switched Paths (LSP) in Multiprotocol Label Switching Traffic Engineering (MPLS-TE) and Generalized MPLS (GMPLS) networks at the request of Path Computation Clients (PCCs). A PCC is shown to be any network component that makes such a request and may be for instance an Optical Switching Element within a Wavelength Division Multiplexing (WDM) network. The PCE, itself, can be located anywhere within the network, and may be within an optical switching element, a Network Management System (NMS) or Operational Support System (OSS), or may be an independent network server. The PCE communications Protocol (PCEP) is the communication protocol used between PCC and PCE, and may also be used between cooperating PCEs. [RFC4657] sets out the common protocol requirements for PCEP. Additional application-specific requirements for PCEP are deferred to separate documents. This document provides the PCEP extension for the support of Routing and Assignment (RWA) in Wavelength Switched Optical Networks (WSON) based on the requirements specified in [PCE-RWA]. WSON refers to WDM based optical networks in which switching is performed selectively based on the wavelength of an optical signal. WSONs can be transparent (A transparent optical network is made up of optical devices that can switch but not convert from one wavelength to another, all within the optical domain) or translucent (regenerators are sparsely placed in the network). A LSC Label Switched Path (LSP) may span one or several transparent segments, which are delimited by 3R regenerators (typically with electronic regenerator and wavelength conversion). Each transparent segment or path in WSON is referred to as an optical path. An optical path may span multiple fiber links and the path should be assigned the same wavelength for each link. In such case, the optical path is Lee & Casellas Expires August 18, 2011 [Page 3] Internet-Draft PCEP Extension for WSON RWA February 2011 said to satisfy the wavelength-continuity constraint. Note that two optical paths within a WSON LSP need not operate on the same wavelength (due to the wavelength conversion capabilities). Two optical paths that share a common fiber link can not be assigned the same wavelength. To do otherwise would result in both signals interfering with each other. Note that advanced additional multiplexing techniques such as polarization based multiplexing are not addressed in this document since the physical layer aspects are not currently standardized. Therefore, assigning the proper wavelength on a lightpath is an essential requirement in the optical path computation process. When a switching node has the ability to perform wavelength conversion the wavelength-continuity constraint can be relaxed, and an LSC Label Switched Path (LSP) may use different wavelengths on different links along its route from origin to destination. It is, however, to be noted that wavelength converters may be limited due to their relatively high cost, while the number of WDM channels that can be supported in a fiber is also limited. As a WSON can be composed of network nodes that cannot perform wavelength conversion, nodes with limited wavelength conversion, and nodes with full wavelength conversion abilities, wavelength assignment is an additional routing constraint to be considered in all lightpath computation. The remainder of this document uses terminology from [RFC4655]. 2. WSON PCE Architectures and Requirements Figure 1 shows one typical PCE based implementation, which is referred to as Combined Process (R&WA). With this architecture, the two processes of routing and wavelength assignment are accessed via a single PCE. This architecture is the base architecture from which the requirements have been specified in [PCE-RWA] and the PCEP extensions that are going to be specified in this document based on this architecture. +----------------------------+ +-----+ | +-------+ +--+ | | | | |Routing| |WA| | | PCC |<----->| +-------+ +--+ | | | | | +-----+ | PCE | +----------------------------+ Figure 1 Combined Process (R&WA) architecture Lee & Casellas Expires August 18, 2011 [Page 4] Internet-Draft PCEP Extension for WSON RWA February 2011 2.1. Encoding of a new RWA path request The current RP object is used to indicate routing related information in a new path request per [RFC5440]. Since a new RWA path request involves both routing and wavelength assignment, the wavelength assignment related information in the request SHOULD be coupled in the path request. The Wavelength Assignment (WA) object is used to indicate wavelength specific request in the path request. The format of a PCReq message after incorporating the WA object is as follows: ::= [] Where: ::=[] ::= [other optional objects...] Note: if WA object is present in the request, the WA object MUST be encoded after the ENDPOINTS object. The format of the Wavelength Assignment (WA) object body 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags |O |E| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Request-ID-number | Lee & Casellas Expires August 18, 2011 [Page 5] Internet-Draft PCEP Extension for WSON RWA February 2011 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // Optional TLVs // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 10: WA Object Body Format Flags (32 bits) The following new flags SHOULD be defined o E (Explicit - 1 bit): When E bit is set to 1, this indicates that the label assigned by the PCE must be explicit. That is, the selected way to convey the allocated wavelength is by means of Explicit Label Control (ELC) [RFC4003] for each hop of a computed LSP. Otherwise, the label assigned by the PCE needs not be explicit (i.e., in the form of label sets). This is to allow the distributed WA. o O (Order - 2 bit): O bit is used to indicate the wavelength policy constraint in regard to the order of wavelength assignment The following indicators should be defined: 00 - Reserved 01 - Random Assignment 10 - First Fit (FF) in descending Order 11 - First Fit (FF) in ascending Order Request-ID-number is same as that in the RP object. 2.1.1. Wavelength Range Constraint TLV For any request that contains a wavelength assignment object, the requester (PCC) MUST be able to specify a restriction on the wavelengths to be used. This restriction is to be interpreted by the PCE as a constraint on the tuning ability of the origination laser transmitter or on any other maintenance related constraints. Note that if the LSP LSC spans different segments, the PCE MUST have mechanisms to know the tunability restrictions of the involved wavelength converters / regenerators. Lee & Casellas Expires August 18, 2011 [Page 6] Internet-Draft PCEP Extension for WSON RWA February 2011 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Format | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Link Identifier | | . . . | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Wavelength [1] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ // . . . . // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Wavelength [N] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Format: The format of the link identifier (32 bits) 0 -- Reserved 1 -- Local Interface IPv4 Address 2 -- Local Interface IPv6 Address 4 -- Unnumbered Interface ID The link identifier field can be an IPv4, IPv6 or unnumbered interface ID and are encoded as follows: IPv4 prefix Subobject 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |X| Type = 1 | Length | IPv4 address (4 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv4 address (continued) | Prefix Length | Attribute | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IPv6 prefix Subobject Lee & Casellas Expires August 18, 2011 [Page 7] Internet-Draft PCEP Extension for WSON RWA February 2011 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |X| Type = 2 | Length | IPv6 address (16 bytes) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv6 address (continued) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv6 address (continued) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv6 address (continued) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv6 address (continued) | Prefix Length | Attribute | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Unnumbered Interface ID Subobject 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |X| Type = 4 | Length | Reserved | Attribute | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TE Router ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The Wavelength is defined in [Lambda-Label] 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Grid | C.S | Identifier | n | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ See [Lambda-Label] for a description of Grid, C.S, Identifier and n. Lee & Casellas Expires August 18, 2011 [Page 8] Internet-Draft PCEP Extension for WSON RWA February 2011 Note that each 32 bit Wavelength Field is designated to represent one wavelength restriction on the associated link identifier. 2.2. Encoding of a RWA Path Reply The ERO is used to encode the path of a TE LSP through the network. The ERO is carried within a given path of a PCEP response, which is in turn carried in a PCRep message to provide the computed TE LSP if the path computation was successful. The preferred way to convey the allocated wavelength is by means of Explicit Label Control (ELC) [RFC4003]. In order to encode wavelength assignment, the Wavelength Assignment (WA) Object needs to be employed to be able to specify wavelength assignment. Since each segment of the computed optical path is associated with wavelength assignment, the WA Object should be aligned with the ERO object. The format of a PCEP response after incorporating the WA object is as follows: ::= [] [] [] ::=[] ::= where: ::=[] [] [] [] [] Lee & Casellas Expires August 18, 2011 [Page 9] Internet-Draft PCEP Extension for WSON RWA February 2011 The Wavelength Assignment (WA) Object is defined 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Flags |O |E| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Request-ID-number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // Optional TLVs // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 11: WA Object Body Format Flags (32 bits) The following new flags SHOULD be defined o E (Explicit - 1 bit): When E bit is set to 1, this indicates that the label assigned by the PCE is explicit in response to the original request. In such case, there will be only one wavelength assigned to the segment of the path. Otherwise, the label assigned by the PCE is in the form of label sets (i.e., there is a set of multiple wavelengths). In such case, the final assignment of wavelength will be done by the nodes in a distributed fashion. o O (Order - 2 bit): O bit is used to indicate the wavelength policy constraint applied in choosing the wavelength for the segment of the path. This only applied when E bit is set to 1. 01 - Random Assignment 10 - First Fit (FF) in descending Order 11 - First Fit (FF) in ascending Order The Request-ID-Number is the same as that in the WA Object in the Path Request message (See Section 2.1.) Lee & Casellas Expires August 18, 2011 [Page 10] Internet-Draft PCEP Extension for WSON RWA February 2011 2.2.1. Wavelength Range Constraint TLV This TLV is used as a part of optional TLV in the Wavelength Assignment (WA) Object defined in the previous section. The purpose of this TLV is to specify the wavelength assignment for the segment of the computed path. If E bit is set to 1 in the WA Object, then there will be only one entry for the wavelength field. If E bit is set to 0, then there will be multiple wavelength fields. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Format | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Link Identifier | | . . . | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Wavelength [1] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ // . . . . // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Wavelength [N] | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The meaning of each field has been defined in Section 2.1.1. 2.3. Error Indicator To indicate errors associated with the RWA request, a new Error Type (TDB) and subsequent error-values are defined as follows for inclusion in the PCEP-ERROR Object: A new Error-Type (TDB) and subsequent error-values are defined as follows: Lee & Casellas Expires August 18, 2011 [Page 11] Internet-Draft PCEP Extension for WSON RWA February 2011 o Error-Type=TBD; Error-value=1: if a PCE receives a RWA request and the PCE is not capable of processing the request due to insufficient memory, the PCE MUST send a PCErr message with a PCEP-ERROR Object (Error-Type=TDB) and an Error-value(Error- value=1). The PCE stops processing the request. The corresponding RWA request MUST be cancelled at the PCC. o Error-Type=TBD; Error-value=2: if a PCE receives a RWA request and the PCE is not capable of RWA computation, the PCE MUST send a PCErr message with a PCEP-ERROR Object (Error-Type=15) and an Error-value (Error-value=2). The PCE stops processing the request. The corresponding RWA computation MUST be cancelled at the PCC. 2.4. NO-PATH Indicator To communicate the reason(s) for not being able to find RWA for the path request, the NO-PATH object can be used in the PCRep message. The format of the NO-PATH object body is defined in [RFC5440]. The object may contain a NO-PATH-VECTOR TLV to provide additional information about why a path computation has failed. Two new bit flags are defined to be carried in the Flags field in the NO-PATH-VECTOR TLV carried in the NO-PATH Object. o Bit TDB: When set, the PCE indicates no feasible route was found that meets all the constraints associated with RWA. o Bit TDB: When set, the PCE indicates that no wavelength was assigned to at least one hop of the route in the response. 3. Manageability Considerations Manageability of WSON Routing and Wavelength Assignment (RWA) with PCE must address the following considerations: 3.1. Control of Function and Policy In addition to the parameters already listed in Section 8.1 of [PCEP], a PCEP implementation SHOULD allow configuring the following PCEP session parameters on a PCC: Lee & Casellas Expires August 18, 2011 [Page 12] Internet-Draft PCEP Extension for WSON RWA February 2011 o The ability to send a WSON RWA request. In addition to the parameters already listed in Section 8.1 of [PCEP], a PCEP implementation SHOULD allow configuring the following PCEP session parameters on a PCE: o The support for WSON RWA. o A set of WSON RWA specific policies (authorized sender, request rate limiter, etc). These parameters may be configured as default parameters for any PCEP session the PCEP speaker participates in, or may apply to a specific session with a given PCEP peer or a specific group of sessions with a specific group of PCEP peers. 3.2. Information and Data Models, e.g. MIB module Extensions to the PCEP MIB module defined in [PCEP-MIB] should be defined, so as to cover the WSON RWA information introduced in this document. A future revision of this document will list the information that should be added to the MIB module. 3.3. Liveness Detection and Monitoring Mechanisms defined in this document do not imply any new liveness detection and monitoring requirements in addition to those already listed in section 8.3 of [RFC5440]. 3.4. Verifying Correct Operation Mechanisms defined in this document do not imply any new verification requirements in addition to those already listed in section 8.4 of [RFC5440] 3.5. Requirements on Other Protocols and Functional Components The PCE Discovery mechanisms ([RFC5089] and [RFC5088]) may be used to advertise WSON RWA path computation capabilities to PCCs. Lee & Casellas Expires August 18, 2011 [Page 13] Internet-Draft PCEP Extension for WSON RWA February 2011 3.6. Impact on Network Operation Mechanisms defined in this document do not imply any new network operation requirements in addition to those already listed in section 8.6 of [PCEP]. 4. Security Considerations This document has no requirement for a change to the security models within PCEP [PCEP]. However the additional information distributed in order to address the RWA problem represents a disclosure of network capabilities that an operator may wish to keep private. Consideration should be given to securing this information. 5. IANA Considerations A future revision of this document will present requests to IANA for codepoint allocation. 6. Acknowledgments The authors would like to thank Adrian Farrel for many helpful comments that greatly improved the contents of this draft. This document was prepared using 2-Word-v2.0.template.dot. 7. References 7.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC3471] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) Signaling Functional Description", RFC 3471, January 2003. Lee & Casellas Expires August 18, 2011 [Page 14] Internet-Draft PCEP Extension for WSON RWA February 2011 [RFC3473] Berger, L., Ed., "Generalized Multi-Protocol Label Switching (GMPLS) Signaling Resource ReserVation Protocol- Traffic Engineering (RSVP-TE) Extensions", RFC 3473, January 2003. [RFC3477] Kompella, K. and Y. Rekhter, "Signalling Unnumbered Links in Resource ReSerVation Protocol - Traffic Engineering (RSVP-TE)", RFC 3477, January 2003. [RFC4003] Berger, L., "GMPLS Signaling Procedure for Egress Control", RFC 4003, February 2005. [RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path Computation Element (PCE)-Based Architecture", RFC 4655, August 2006. [RFC4657] Ash, J. and J. Le Roux, "Path Computation Element (PCE) Communication Protocol Generic Requirements", RFC 4657, September 2006. [RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation Element (PCE) communication Protocol", RFC 5440, March 2009. 7.2. Informative References [WSON-Frame] Lee, Y. and Bernstein, G. (Editors), and W. Imajuku, "Framework for GMPLS and PCE Control of Wavelength Switched Optical Networks", draft-ietf-ccamp-rwa-wson-framework, work in progress. [PCE-RWA] Lee, Y., et. al., "PCEP Requirements for WSON Routing and Wavelength Assignment", draft-ietf-pce-wson-routing- wavelength, work in progress. [Lambda-Label] Tomohiro, O. and D. Li, "Generalized Labels for Lambda-Switching Capable Label Switching Routers", draft- ietf-ccamp-gmpls-g-694-lambda-labels, work in progress. 8. Contributors Lee & Casellas Expires August 18, 2011 [Page 15] Internet-Draft PCEP Extension for WSON RWA February 2011 Authors' Addresses Young Lee (Ed.) Huawei Technologies 1700 Alma Drive, Suite 100 Plano, TX 75075, USA Phone: (972) 509-5599 (x2240) Email: leeyoung@huawei.com Ramon Casellas (Ed.) 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Disclaimer of Validity All IETF Documents and the information contained therein 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 Lee & Casellas Expires August 18, 2011 [Page 16] Internet-Draft PCEP Extension for WSON RWA February 2011 WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION THEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Lee & Casellas Expires August 18, 2011 [Page 17]