Network Working Group Y. Lee Internet Draft Huawei Intended status: Standard Track G. Bernstein Expires: May 2008 Grotto Networking October 29, 2007 Path Computation Element Communication Protocol (PCEP) Requirements and Extensions for the Support of Wavelength Switched Optical Networks draft-lee-pce-wson-routing-wavelength-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. This document may not be modified, and derivative works of it may not be created, except to publish it as an RFC and to translate it into languages other than English. 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 May 1, 2007. Copyright Notice Copyright (C) The IETF Trust (2007). Abstract Lee & Bernstein Expires May 1, 2008 [Page 1] Internet-Draft PCEP Extension for WSON November 2007 This memo provides application-specific PCEP requirements and protocol enhancements for the support of Wavelength Switched Optical Networks (WSON). Lightpath provisioning in WSONs requires a routing and wavelength assignment (RWA) process. Different computational architectures for the RWA process are given and the PCEP extensions needed to support these architectures are defined. 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. Terminology.................................................3 2. Introduction................................................4 3. Background: RWA Computation Architectures....................4 4. PCECP Requirements..........................................5 4.1. RWA Computation Options.................................6 4.2. Timeliness Characteristics of lightpath.................7 4.3. Duration of lightpath...................................7 4.4. Optimization Degree.....................................8 4.5. Wavelength Selection Preference.........................8 4.6. Wavelength Assignment and Wavelength Set Information.....9 4.7. Lightpath Route Parameters..............................9 5. Protocol extensions for support of WSON Routing and Wavelength Assignment (RWA)...............................................9 5.1. RWA Computation Options.................................9 5.2. Lightpath Route Parameter TLV..........................11 5.3. Wavelength Selection Preferences.......................12 5.4. Wavelength Suggestion/Restriction TLV..................14 5.5. Error Indicator........................................14 5.6. NO-PATH Indicator......................................14 6. Manageability Considerations................................15 6.1. Control of Function and Policy.........................15 6.2. Information and Data Models, e.g. MIB module...........16 6.3. Liveness Detection and Monitoring......................16 6.4. Verifying Correct Operation............................16 6.5. Requirements on Other Protocols and Functional Components16 6.6. Impact on Network Operation............................16 7. Security Considerations.....................................17 Lee & Bernstein Expires May 1, 2008 [Page 2] Internet-Draft PCEP Extension for WSON November 2007 8. IANA Considerations........................................17 9. Acknowledgments............................................17 10. References................................................17 10.1. Normative References..................................17 10.2. Informative References................................18 Author's Addresses............................................18 Intellectual Property Statement................................19 Disclaimer of Validity........................................19 1. Terminology The terminology explained herein complies with [RFC4655]. PCC: Path Computation Client: Any client application requesting a path computation to be performed by a Path Computation Element. PCE: Path Computation Element: An entity (component, application or network node) that is capable of computing a network path or route based on a network graph and applying computational constraints. TED: Traffic Engineering Database which contains the topology and resource information of the domain. The TED may be fed by IGP extensions or potentially by other means. PCECP: The PCE Communication Protocol: PCECP is the generic abstract idea of a protocol that is used to communicate path computation requests a PCC to a PCE, and to return computed paths from the PCE to the PCC. The PCECP can also be used between cooperating PCEs. PCEP: The PCE communication Protocol: PCEP is the actual protocol that implements the PCECP idea. RWA: Routing and Wavelength Assignment WSON: Wavelength Switched Optical Networks: WDM based optical networks in which switching is performed selectively based on the center wavelength of an optical signal. 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 [RFC2119]. These terms are also used in the parts of this document that specify requirements for clarity of specification of those requirements. Lee & Bernstein Expires May 1, 2008 [Page 3] Internet-Draft PCEP Extension for WSON November 2007 2. 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 PCCs. A PCC is shown to be any network component that makes such a request and may be for instance an Optical Switching Element with a WDM network. The PCE, itself, can be located anywhere within the network, and may be within an optical switching element, an NMS or Operational Support System (OSS), or may be an independent network server. The PCECP 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 the PCECP. Additional application- specific requirements for PCECP are deferred to separate documents. This document provides a set of application-specific PCECP requirements and protocol enhancements for support of path computation in Wavelength Switched Optical Network (WSON). WSON refers to Wavelength Division Mulitiplexing (WDM) based optical networks in which switching is performed selectively based on the wavelength of an optical signal. The path in WSON is referred to as a lightpath. In order to provision a light path, both routing and wavelength assignment (RWA) are required. 3. Background: RWA Computation Architectures The WSON framework [WSON Frame] document defines the following RWA computation architectures. o Combined RWA --- Both routing and wavelength assignment are performed at a single computational entity. This choice assumes that computational entity has sufficient WSON network link/nodal and topology information to be able to compute RWA. o Separate Routing and WA --- Separate entities perform routing and wavelength assignment. The path obtained from the routing computational entity must be furnished to the entity performing wavelength assignment. o Routing with Distributed WA --- Routing is performed at a computational entity while wavelength assignment is performed in a distributed fashion across the nodes along the path. Lee & Bernstein Expires May 1, 2008 [Page 4] Internet-Draft PCEP Extension for WSON November 2007 For the Combined RWA architecture, there are two possible computing entities: (i) the NE is the computational entity -- in this case, there is no separate PCE as the NE assumes PCE function; (ii) a separate PCE is the computational entity. This document is only concerned with case (ii). In this case, the PCE should perform both routing (R) and wavelength assignment (WA) upon request of the PCC. For the Separate Routing and Wavelength architecture, there can be two variations: o A separate PCE will perform only wavelength assignment (WA) while the NE performs the route calculation based on its local knowledge. In this case, the NE should furnish the route list to the PCE so that the PCE would be able to assign wavelength to the route. o One PCE performs the routing (R) function while another PCE performs the Wavelength Assignment (WA) function in a tandem fashion. The fact that two PCEs are involved (one for Routing and one for Wavelength Assignment (WA)) could be invisible to the original PCC. For the Routing with Distributed WA architecture, the PCE is only responsible for routing (i.e., path computation), not for exact wavelength assignment. The exact assignment of wavelength would be performed at the NEs along the path in a distributed fashion. However, the PCE may choose to limit the wavelengths that can be used (i.e., suggesting the wavelength set to the NEs) 4. PCECP Requirements This section provides the PCECP requirements to support WSON routing and wavelength assignment (RWA) application. The requirements specified in this section are detailed requirements based on high- level specification in the WSON Framework draft [WSON FRAME]. The requirements specified here should be regarded as application- specific requirements and are justifiable based on the extensibility clause found in section 6.1.14 of [RFC4657]: The PCECP MUST support the requirements specified in the application- specific requirements documents. The PCECP MUST also allow extensions as more PCE applications will be introduced in the future. Lee & Bernstein Expires May 1, 2008 [Page 5] Internet-Draft PCEP Extension for WSON November 2007 The PCEP SHOULD support the following capabilities either via creation of new objects and/or modification of existing object where applicable. 4.1. RWA Computation Options The following RWA computation options should be conveyed in the PC Request: o The request is for Wavelength Assignment (WA) only. This case may arise when the NE is capable of route calculation at the node level (e.g., via an IGP-TE) but with no wavelength information available at the node level, or when two PCEs work in tandem with one performing the routing (R) function and another wavelength assignment (WA). In either case, the calculated route list at one computing entity should be supplied in the request message to the other computing entity where WA is applied. o The request is for both Routing and Wavelength Assignment (R+WA). This case may arise when the NE is not capable of both route calculation and wavelength assignment at the node level or a more optimal RWA is desired. o The request is for Routing (R) only. This case may arise when the NE is not capable of route calculation at the node level while wavelength assignment is done at the node level in a distributed fashion. o The request is for Routing (R) with the suggested/restricted wavelength set. This is a variation from the Routing only option. With this option, the PCE computes the route and the candidate wavelengths associated with the route. In this case, the exact wavelength assignment is to be performed at the NE level. The corresponding PC Reply message should include the following information: o An indicator that conveys the original request was for (i) WA only; (ii) R+WA; (iii) R only; (iv) R with the suggested/restricted wavelength set Lee & Bernstein Expires May 1, 2008 [Page 6] Internet-Draft PCEP Extension for WSON November 2007 o The route list and the recommended wavelength(s) to be used for the route. The encoding of this requirement can be fulfilled with the ERO object and ERO Label subobject within the ERO as defined in [RFC3471]. See section 4.6 for details of wavelength label assignment. o In the case of failure to find a proper route or wavelength assigned to the route, proper reasons for the failure should be conveyed: (i) route not found; (ii) wavelength not found (i.e., wavelength blocking); (iii) both route and wavelength not found. 4.2. Timeliness Characteristics of lightpath The request may indicate specific timeliness lightpath characteristics associated with the request: o Time Critical: this type of request is useful for those lightpath establishment requests used for restoration of service or other high priority real time services. o Soft Time Bounds: this type of request is a more typical new connection request. While expected to be responsive, there should be more time to take into account network optimization. o Scheduled: this type of request is useful when the requested lightpath connections are not time critical (i.e., the request is significantly ahead of their intended "in-service" time. It is to be noted that we will not explicitly deal with scheduled case in this document but the optimization can be handled via [PCE-GCO]. The reply should indicate the original timeliness characteristics of the lightpath request with path computation results. 4.3. Duration of lightpath The request may indicate specific lightpath duration information associated with the request. This may be useful to the PCE since it is not worthwhile to optimize lightpaths with relatively short duration as compared to pseudo-static paths. Lee & Bernstein Expires May 1, 2008 [Page 7] Internet-Draft PCEP Extension for WSON November 2007 4.4. Optimization Degree The PC Request Message should indicate the degree of optimization associated with lightpath computation. o Concurrent Optimization: multiple lightpaths requested at one time. o Lightpath(s) and backup lightpath(s) requested at one time. o Sequential Optimization: single lightpath requested at a time. The PC Reply Message should include the original optimization degree associated with the request when replying the path computation results. 4.5. Wavelength Selection Preference The PC Request may indicate the Wavelength Selection Preference to which a path computation request is applied. The Wavelength Selection Preference to be supported at the minimum is: o Random o First Fit o Most Used o Least Loaded o Don't care: default Note that the objective functions to be supported for a single LSP request are listed in [PCEP] and [PCE-OF] and that the objective functions to be supported for a concurrent LSP request are listed in [PCE-GCO] and [PCE-OF]. The PC Reply should indicate which wavelength selection preference has actually been applied. Lee & Bernstein Expires May 1, 2008 [Page 8] Internet-Draft PCEP Extension for WSON November 2007 4.6. Wavelength Assignment and Wavelength Set Information The PCE MUST specify the wavelength assignment and/or wavelength set information in response to the wavelength assignment/wavelength set Request made by the PCC in the PCReq message. If the original request is either for both Routing and Wavelength Assignment or for Wavelength Assignment only, the exact wavelength assignment result can be conveyed to PCC using the ERO object and ERO Label subobject within the ERO. Note that this is not a new requirement. Current PCEP allows this mechanism which is defined as the Label Set mechanism in [RFC3471]. If the original request is for Routing with wavelength suggested/restricted wavelength set, then the Wavelength Set information must be provided to the PCC. 4.7. Lightpath Route Parameters The following Lightpath Route Parameters should be indicated: o Bidirectional Assignment of wavelengths for a bidirectional LSP request. o Possible simultaneous assignment of the same wavelength to primary and backup paths. The PC Reply Message should include the original lightpath route parameter associated with the request when replying the path computation results. 5. Protocol extensions for support of WSON Routing and Wavelength Assignment (RWA) 5.1. RWA Computation Options The PCE has to include the RWA computation option in the PCReq message in order to convey a particular computation option. To support such indication a new flag, the RC flag, is defined in the RP (Request Parameter) Object. The PCE also has to include the Directionality of Wavelength Assignment indicator when the request is Lee & Bernstein Expires May 1, 2008 [Page 9] Internet-Draft PCEP Extension for WSON November 2007 for a bidirectional TE LSP. To support such indication a new flag, I flag, is defined in the RP Object. The RC flag and I flag are defined in the RP (Request Parameter) object 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | Flags |I|RC|D|M|F|O|B|R| Pri | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Request-ID-number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // Optional TLV(s) // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1 RP object body format in the PCReq Message RC bits (Routing wavelength Computation bits - 2 bits): o 11: Request is for both R (Routing) and Wavelength Assignment (WA). o 01: Request is for Wavelength Assignment (WA) only. o 10: Request is for Routing (R) with suggested/restricted Wavelength Set o 00: Request is for Routing (R) only. When RC bit is set to 11 in a PCReq message, the requesting PCC requires the PCE to provide in the PCRep message the assigned wavelength associated with the computed path. This request is for both Routing (R) and Wavelength Assignment (WA). When RC bit is set to 01 in a PCReq message, the requesting PCC requires the PCE only to provide wavelength assignment (WA). In such case, the PCC must provide the already computed route (as indicated by the ERO and the Bandwidth Object following the RP object) to which the PCE would assign the wavelengths. Note that this option is to fulfill one of the RWA computational architectures, namely, the Separate Routing and WA option. Lee & Bernstein Expires May 1, 2008 [Page 10] Internet-Draft PCEP Extension for WSON November 2007 When RC bit is set to 10, then the PCE is expected to provide some suggestive or restrictive wavelength information associated with the route. When RC bit is set to either 11, 01 or 10, then additional parameters associated with the requested lightpath should be provided in optional lightpath Route Parameter TLV (as specified in Section 4.7) within the RP object. See Section 5.2 for the encoding of Lightpath Route Parameter TLV. When B bit is set in the RP object in a PCReq message, this indicates that the path computation request relates to a bidirectional TE LSP [PCEP]. In such case, a new flag, I flag, should be defined in the RP object should be defined in order to indicate that a bidirectional assignment of wavelength be required for the bidirectional TE LSP. I bit (dIrectionality bit - 1 bit): When set, the request is a bidirectional wavelength assignment. Otherwise, the request is a unidirectional wavelength assignment. The RP object in the PC Reply message should properly indicate the original request for the RWA Computation (RC) bit and I bit that have actually been applied by the PCE. The actual route list and wavelength assignment is to be found in the ERO object and within an ERO an ERO Label subobject. An ERO Label subobject can be used to indicate the wavelength to be used at a particular node. Note that current GMPLS signaling supports an explicit route object (ERO) and within an ERO an ERO Label subobject. 5.2. Lightpath Route Parameter TLV When the RC bit is set to either 11, 01 or 10 in the RP object associated with PC Req message, then the following TLV should be included as part of the RP object within the PC Request message. The format of the Lightpath Route Parameter TLV is as follows: Lee & Bernstein Expires May 1, 2008 [Page 11] Internet-Draft PCEP Extension for WSON November 2007 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Bidirectional Assignment of wavelengths | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Same wavelength to primary and backup paths | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type To be defined by IANA (suggested value = ) Length Variable Value Bidirectional Assignment of wavelengths (0 or 1) Same Wavelength to primary and backup (0 or 1) Figure 2 The Lightpath Route Parameter TLV in the RP object in the PC Rep Message 5.3. Wavelength Selection Preferences When the RC (RWA Computation) option is associated with computing wavelength assignment in the RP object of the PC Request message, then the following Wavelength Selection Preference TLV may be included in the RP object as an optional TLV. The format of the Wavelength Selection Preference TLV is as follows: Lee & Bernstein Expires May 1, 2008 [Page 12] Internet-Draft PCEP Extension for WSON November 2007 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Wavelength Selection Preference | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | TDB | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type To be defined by IANA (suggested value = ) Length Variable Value Wavelength Selection Preference Figure 3 The Wavelength Selection/Assignment Preferences TLV in the RP object in the PC Rep Message Five wavelength selection preferences are defined in this document and their identifier should be assigned by IANA (suggested value) Function Code Description 1 Random 2 First Fit 3 Most Used 4 Least Loaded 5 Don't Care The Wavelength Selection Preference TLV should also be included in the RP object in the PC Reply message to indicate which wavelength selection preference has actually been applied by the PCE in its wavelength assignment procedure. Lee & Bernstein Expires May 1, 2008 [Page 13] Internet-Draft PCEP Extension for WSON November 2007 5.4. Wavelength Suggestion/Restriction TLV With the Routing with Distributed Wavelength Assignment option, the PC Reply should specify the wavelength set information in response to the wavelength assignment/wavelength set Request made by the PCC in the PCReq message if so requested by the setting of the RC bit in the RP object in the PCReq message. We refer to this information as wavelength restriction TLV. The encoding of wavelength Suggestion/Restriction TLV is to be provided in the next version. 5.5. Error Indicator To indicate errors associated with the RWA request, a new Error-Type (15) and subsequent error-values are defined as follows for inclusion in the PCEP-ERROR object: A new Error-Type (15) and subsequent error-values are defined as follows: Error-Type=15 and Error-Value=1: if a PCE receives a RWA computation request and the PCE is not capable of RWA, the PCE MUST send a PCErr message with a PCEP ERROR object (Error-Type=15) and an Error-Value (Error-Value=1). The corresponding RWA computation request MUST be cancelled. To indicate an error associated with policy violation, a new error value "RWA not allowed" should be added to an existing error code for policy violation (Error-Type=6) as defined in [PCEP]. Error-Type=6; Error-Value=3: if a PCE receives a RWA computation request which is not compliant with administrative privileges (i.e., the PCE policy does not support RWA), the PCE sends a PCErr message with a PCEP-ERROR Object (Error-Type=6) and an Error-Value (Error- Value=3). The corresponding RWA computation MUST be cancelled. 5.6. NO-PATH Indicator To communicate the reason(s) for not being able to find RWA computation, the NO-PATH object can be used in the PCRep message. The format of the NO-PATH object body is as follows: Lee & Bernstein Expires May 1, 2008 [Page 14] Internet-Draft PCEP Extension for WSON November 2007 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |C| Flags | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // Optional TLV(s) // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 4 NO-PATH object format Flags (16 bits). The C flag is defined in [PCEP]. Two new bit flags are defined in the NO-PATH-VECTOR TLV carried in the NO-PATH Object: 0x08: when set, the PCE indicates that no path was found. 0x10: when set, the PCE indicates that no wavelength was found associated with RWA computation in the PCRep message. 6. Manageability Considerations Manageability of WSON Routing and Wavelength Assignment (RWA) with PCE must address the following considerations: 6.1. 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: 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: Lee & Bernstein Expires May 1, 2008 [Page 15] Internet-Draft PCEP Extension for WSON November 2007 o The support for WSON RWA. o The maximum number of synchronized path requests associated with WSON RWA per request message. 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. 6.2. 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. 6.3. Liveness Detection and Monitoring Mechanisms defined in this draft does not imply any new liveness detection and monitoring requirements in addition to those already listed in section 8.3 of [PCEP]. 6.4. Verifying Correct Operation Mechanisms defined in this draft does not imply any new verification requirements in addition to those already listed in section 8.4 of [PCEP] 6.5. Requirements on Other Protocols and Functional Components The PCE Discovery mechanisms ([ISIS PCED] and [OSPF PCED]) may be used to advertise WSON RWA path computation capabilities to PCCs. 6.6. Impact on Network Operation Mechanisms defined in this draft does not imply any new network operation requirements in addition to those already listed in section 8.6 of [PCEP]. Lee & Bernstein Expires May 1, 2008 [Page 16] Internet-Draft PCEP Extension for WSON November 2007 7. 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. 8. IANA Considerations A future revision of this document will present requests to IANA for codepoint allocation. 9. Acknowledgments 10. References 10.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2234] Crocker, D. and Overell, P.(Editors), "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, Internet Mail Consortium and Demon Internet Ltd., November 1997. [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. [PCEP] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation Element (PCE) communication Protocol (PCEP) - Version 1", draft-ietf-pce-pcep, work in progress. Lee & Bernstein Expires May 1, 2008 [Page 17] Internet-Draft PCEP Extension for WSON November 2007 [PCE-OF] Le Roux, JL., Vasseur, JP., and Y. Lee, "Objective Function encoding in Path Computation Element communication and discovery protocols", draft-ietf-pce-pce-of, work in progress. [PCE-GCO] Y. Lee, J.L. Le Roux, D. King, and E. Oki, "Path Computation Element Communication Protocol (PCECP) Requirements and Protocol Extensions In Support of Global Concurrent Optimization", draft-ietf-pce-global-concurrent- optimization, work in progress. 10.2. Informative References [WSON-FRAME] Bernstein, G. and Lee, Y. (Editors), and W. Imajuku, "Framework for GMPLS and PCE Control of Wavelength Switched Optical Networks", draft-bernstein-ccamp-wavelength- switched, work in progress. [ISIS-PCED] Le Roux, J. and JP. Vasseur, "IS-IS protocol extensions for Path Computation Element (PCE) Discovery", draft-ietf- pce-disco-proto-isis, work in progress. [OSPF-PCED] Le Roux, J. and JP. Vasseur, "OSPF protocol extensions for Path Computation Element (PCE) Discovery", draft-ietf- pce-disco-proto-ospf, work in progress. Author's Addresses Young Lee (ed.) Huawei Technologies 1700 Alma Drive, Suite 100 Plano, TX 75075, USA Phone: (972) 509-5599 (x2240) Email: ylee@huawei.com Lee & Bernstein Expires May 1, 2008 [Page 18] Internet-Draft PCEP Extension for WSON November 2007 Greg Bernstein (ed.) Grotto Networking Fremont, CA, USA Phone: (510) 573-2237 Email: gregb@grotto-networking.com 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, THE IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Copyright Statement Copyright (C) The IETF Trust (2007). Lee & Bernstein Expires May 1, 2008 [Page 19] Internet-Draft PCEP Extension for WSON November 2007 This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Lee & Bernstein Expires May 1, 2008 [Page 20]