Network work group Fatai Zhang Internet Draft Young Lee Intended status: Standards Track Jianrui Han Huawei G. Bernstein Grotto Networking Yunbin Xu CATR Expires: September 4, 2010 March 5, 2010 OSPF Extensions in Support of Routing and Wavelength Assignment (RWA) in Wavelength Switched Optical Networks (WSONs) draft-zhang-ccamp-rwa-wson-routing-ospf-03.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." 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 September 4, 2010. Abstract Expires Septemper 2010 [Page 1] Internet-Draft OSPF Extensions for WSON March 2010 This document describes OSPF routing protocols extensions to support Routing and Wavelength Assignment (RWA) in Wavelength Switched Optical Networks (WSON) under the control of Generalized MPLS (GMPLS). 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 [RFC2119]. Table of Contents 1. Introduction......................................... 2 2. Node Information..................................... 3 2.1. Connectivity Matrix..............................4 3. Link Information..................................... 4 3.1. Port Label Restrictions .........................5 3.2. Available Labels.................................5 3.3. Shared Backup Labels.............................6 4. Routing Procedures....................................6 5. Security Considerations...............................7 6. IANA Considerations...................................7 6.1. Node Information.................................7 6.2. Link Information.................................7 7. References............................................7 8. Authors' Addresses....................................9 Acknowledgment ..........................................11 1. Introduction [WSON-Frame] provides a framework for applying GMPLS [RFC3945] and the Path Computation Element (PCE) architecture [RFC4655] to the control of WSONs to address the RWA problem. [WSON-Info] describes an information model that specifies the information needed at various points in a WSON in order to compute paths and establish Label Switched Paths (LSPs). Based on the information model of [WSON-Info], [GEN-Encode] and [RWA-Encode] provide efficient protocol-independent encodings of the information needed by the RWA process in a WSON. Such encodings can be used to extend GMPLS signaling and routing protocols. This document provides RWA OSPF extensions based on [GEN-Encode] which provides encodings of the information needed by the routing and label assignment process in technologies such as WSON but that are Zhang Expires September 2010 [Page 2] Internet-Draft OSPF Extensions for WSON March 2010 potentially applicable to a wider range of technologies. Additional RWA OSPF extensions based on [RWA-Encode] which provides encodings of the information specific to WSON technologies such as signal compatibility and wavelength resource encodings are addressed in the other document [WSON-COM-OSPF]. This document defines extensions to the OSPF routing protocol to enhance the Traffic Engineering (TE) properties of GMPLS TE which are defined in [RFC3630], [RFC4202], and [RFC4203]. The enhancements to the Traffic Engineering (TE) properties of GMPLS TE links can be announced in OSPF TE LSAs. The TE LSA, which is an opaque LSA with area flooding scope [RFC3630], has only one top-level Type/Length/Value (TLV) triplet and has one or more nested sub-TLVs for extensibility. The top-level TLV can take one of three values (1) Router Address [RFC3630], (2) Link [RFC3630], (3) Node Attribute [OSPF-Node]. In this document, we enhance the sub-TLVs for the Link TLV and Node Attribute TLV in support of RWA in WSON under the control of GMPLS. The detail encoding of OSPF extensions is not redefined in this document. [GEN-Encode] provides encoding detail. No consideration of optical impairment routing related information is included in this document. 2. Node Information According to [WSON-Info] and [GEN-Encode], the node information about WSON nodes includes Node ID, connectivity matrix. Except for the Node ID which should comply with Routing Address described in [RFC3630], the other pieces of information are defined in this document. [OSPF-Node] defines a new top TLV named the Node Attribute TLV which carries attributes related to a router/node. This Node Attribute TLV contains one or more sub-TLVs. Per [GEN-Encode], we have identified the following new Sub-TLVs to the Node Attribute TLV. Detail description for each newly defined Sub-TLV is provided in subsequent sections: Sub-TLV Type Length Name TBD variable Connectivity Matrix In WSON networks, generally the sub-TLVs above is optional, which depends on the control plane implementations. Usually, Connectivity Matrix sub-TLV may appear in the LSAs because WSON switches are Zhang Expires September 2010 [Page 3] Internet-Draft OSPF Extensions for WSON March 2010 asymmetric at present. It is assumed that the switches are symmetric switching, if there is no Connectivity Matrix sub-TLV in the LSAs. 2.1. Connectivity Matrix It is necessary to identify which ingress ports and wavelengths can be connected to (the same wavelength on) a specific egress port, because the switching devices in a WSON are highly asymmetric. The Connectivity Matrix is used to identify these restrictions, which can represent either the potential connectivity matrix for asymmetric switches (e.g. ROADMs and such) or fixed connectivity for an asymmetric device such as a multiplexer as defined in [WSON-Info]. The Connectivity Matrix is a sub-TLV (the type is TBD by IANA) of the Node Attribute TLV. The length is the length of value field in octets. The meaning and format of this sub-TLV are defined in Section 5.3 of [GEN-Encode]. One sub-TLV contains one matrix. The Connectivity Matrix sub-TLV may occur more than once to contain multi-matrices within the Node Attribute TLV. 3. Link Information The most common link sub-TLVs nested to link top-level TLV are already defined in [RFC3630], [RFC4203]. For example, Link ID, Administrative Group, Interface Switching Capability Descriptor (ISCD), Link Protection Type, Shared Risk Link Group Information (SRLG), and Traffic Engineering Metric are among the typical link sub-TLVs. For WSONs, per [WSON-Info] and [GEN-Encode], we add the following additional link sub-TLVs to the link-TLV in this document. Sub-TLV Type Length Name TBD variable Port Label Restrictions TBD variable Available Labels TBD variable Shared Backup Labels In WSON networks, generally all the sub-TLVs above are optional, which depends on the control plane implementations. It is default no restrictions on wavelength, so Port Label Restrictions sub-TLV may not appear in the LSAs. In order to be able to compute RWA, Available Zhang Expires September 2010 [Page 4] Internet-Draft OSPF Extensions for WSON March 2010 Labels sub-TLV may appear in the LSAs. Without available wavelength information, path computation need guess what lambdas may be available (high blocking probability or distributed wavelength assignment may be used). Shared Backup Labels sub-TLV SHOULD not appear in the LSAs, if there is no wavelength backup functionality in the WSON networks. 3.1. Port Label Restrictions Port Label Restrictions describes the wavelength restrictions that the link and various optical devices such as OXCs, ROADMs, and waveband multiplexers may impose on a port in WSON. These restrictions represent what wavelength may or may not be used on a link and are relatively static. The detailed information about Port label restrictions is described in [WSON-Info]. The Port Label Restrictions is a sub-TLV (the type is TBD by IANA) of the Link TLV. The length is the length of value field in octets. The meaning and format of this sub-TLV are defined in Section 5.4 of [GEN-Encode]. The Port Label Restrictions sub-TLV may occur more than once to specify a complex port constraint within the link TLV. 3.2. Available Labels Available Labels indicates the wavelengths available for use on a link as described in [GEN-Encode] in WSON. The Available Labels is a sub-TLV (the type is TBD by IANA) of the Link TLV. The length is the length of value field in octets. The meaning and format of this sub- TLV are defined in Section 5.1 of [GEN-Encode]. The Available Labels sub-TLV may occur at most once within the link TLV. Note that there are five approaches for Wavelength (Label) Set which is used to represent the Available Labels described in [GEN-Encode]. Considering that the continuity of the available or unavailable wavelength set can be scattered for the dynamic wavelength availability, so it may burden the routing to reorganize the wavelength set information when the Inclusive (/Exclusive) List (/Range) approaches are used to represent Available Wavelengths information. Therefore, it is RECOMMENDED that only the Bitmap Set be used for representation Available Wavelengths information. The "Base Label" and "Last Label" in label set defined in [GEN-Encode] corresponds to base wavelength label and last wavelength label in WSON, the format of which is described as follows: Zhang Expires September 2010 [Page 5] Internet-Draft OSPF Extensions for WSON March 2010 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. | Reserved | n | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The detailed information related to wavelength label can be referred to [Lambda-Labels] 3.3. Shared Backup Labels Shared Backup Labels indicates the wavelengths available for shared backup use on a link as described in [GEN-Encode] in WSON. The Shared Backup Labels is a sub-TLV (the type is TBD by IANA) of the Link TLV. The length is the length of value field in octets. The meaning and format of this sub-TLV are defined in Section 5.2 of [GEN-Encode]. The Shared Backup Labels sub-TLV may occur at most once within the link TLV. 4. Routing Procedures All the sub-TLVs are nested to top-level TLV(s) and contained in Opaque LSAs. The flooding of Opaque LSAs must follow the rules specified in [RFC2328], [RFC2370], [RFC3630], [RFC4203] and [OSPF- Node]. In the WSON networks, the node information and link information can be classified as two kinds: one is relatively static information such as Node ID, Connectivity Matrix information; the other is dynamic information such as Available Wavelengths information. [GEN-Encode] give recommendations of typical usage of previously defined sub-TLVs which contain relatively static information and dynamic information. An implementation SHOULD take measures to avoid frequent updates of relatively static information when the relatively static information is not changed. A mechanism MAY be applied such that static information and dynamic information are contained in separate Opaque LSAs to avoid unnecessary updates of static information when dynamic information is changed. Note that as with other TE information, an implementation SHOULD take measures to avoid rapid and frequent updates of routing information that could cause the routing network to become swamped. A threshold mechanism MAY be applied such that updates are only flooded when a number of changes have been made to the wavelength availability Zhang Expires September 2010 [Page 6] Internet-Draft OSPF Extensions for WSON March 2010 information within a specific time. Such mechanisms MUST be configurable if they are implemented. 5. Security Considerations This document does not introduce any further security issues other than those discussed in [RFC 3630], [RFC 4203]. 6. IANA Considerations [RFC3630] says that the top level Types in a TE LSA and Types for sub-TLVs for each top level Types must be assigned by Expert Review, and must be registered with IANA. IANA is requested to allocate new Types for the sub-TLVs as defined in Sections 2.1, 3.1, 3.2 and 3.3 as follows: 6.1. Node Information This document introduces the following sub-TLVs of Node Attribute TLV (Value TBD, see [OSPF-Node]) Type sub-TLV TBD Connectivity Matrix 6.2. Link Information This document introduces the following sub-TLVs of TE Link TLV (Value 2) Type sub-TLV TBD Port Label Restrictions TBD Available Labels TBD Shared Backup Labels 7. 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. Zhang Expires September 2010 [Page 7] Internet-Draft OSPF Extensions for WSON March 2010 [RFC3630] Katz, D., Kompella, K., and Yeung, D., "Traffic Engineering (TE) Extensions to OSPF Version 2", RFC 3630, September 2003. [RFC4202] Kompella, K., Ed., and Y. Rekhter, Ed., "Routing Extensions in Support of Generalized Multi-Protocol Label Switching (GMPLS)", RFC 4202, October 2005 [RFC4203] Kompella, K., Ed., and Y. Rekhter, Ed., "OSPF Extensions in Support of Generalized Multi-Protocol Label Switching (GMPLS)", RFC 4203, October 2005. [RFC3945] E. Mannie, Ed., "OGeneralized Multi-Protocol Label Switching (GMPLS) Architecture", RFC 3945, October 2004. [RFC4655] Farrel, A., Vasseur, J.-P., and J. Ash, "A Path Computation Element (PCE)-Based Architecture ", RFC 4655, August 2006. [RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998. [RFC2370] Coltun, R., "The OSPF Opaque LSA Option", RFC 2370, July 1998. [OSPF-Node] R. Aggarwal and K. Kompella, "Advertising a Router's Local Addresses in OSPF TE Extensions", draft-ietf-ospf- te-node-addr, work in progress. [Lambda-Labels] T. Otani, H. Guo, K. Miyazaki, D. Caviglia, " Generalized Labels for Lambda-Switching Capable Label Switching Routers", work in progress: draft- ietf-ccamp-gmpls-g-694-lambda-labels-05.txt, December 2009. [WSON-Frame] Y. Lee, G. Bernstein, W. Imajuku, "Framework for GMPLS and PCE Control of Wavelength Switched Optical Networks (WSON)", work in progress: draft-ietf-ccamp-rwa-WSON- Framework-05.txt, February 2010. [WSON-Info] Y. Lee, G. Bernstein, D. Li, W. Imajuku, "Routing and Wavelength Assignment Information Model for Wavelength Switched Optical Networks", work in progress: draft-ietf- ccamp-rwa-info-07.txt, February 2010. Zhang Expires September 2010 [Page 8] Internet-Draft OSPF Extensions for WSON March 2010 [RWA-Encode]G. Bernstein, Y. Lee, D. Li, W. Imajuku, "Routing and Wavelength Assignment Information Encoding for Wavelength Switched Optical Networks", work in progress: draft-ietf-ccamp-rwa-wson-encode-04.txt, February 2010. [GEN-Encode] G. Bernstein, Y. Lee, D. Li, W. Imajuku, " General Network Element Constraint Encoding for GMPLS Controlled Networks", work in progress: draft-ietf- ccamp-general-constraint-encode-01.txt, March 2010. [WSON-COM-OSPF] Y. Lee, G. Bernstein, "OSPF Enhancement for Signal and Network Element Compatibility for Wavelength Switched Optical Networks", work in progress: draft- ietf-ccamp-wson-signal-compatibility-ospf-00.txt, December 8, 2009. 8. Authors' Addresses Fatai Zhang Huawei Technologies F3-5-B R&D Center, Huawei Base Bantian, Longgang District Shenzhen 518129 P.R.China Phone: +86-755-28972912 Email: zhangfatai@huawei.com Young Lee Huawei Technologies 1700 Alma Drive, Suite 100 Plano, TX 75075 USA Phone: (972) 509-5599 (x2240) Email: ylee@huawei.com Jianrui Han Huawei Technologies Co., Ltd. F3-5-B R&D Center, Huawei Base Bantian, Longgang District Zhang Expires September 2010 [Page 9] Internet-Draft OSPF Extensions for WSON March 2010 Shenzhen 518129 P.R.China Phone: +86-755-28972913 Email: hanjianrui@huawei.com Greg Bernstein Grotto Networking Fremont CA, USA Phone: (510) 573-2237 Email: gregb@grotto-networking.com Yunbin Xu China Academy of Telecommunication Research of MII 11 Yue Tan Nan Jie Beijing, P.R.China Phone: +86-10-68094134 Email: xuyunbin@mail.ritt.com.cn Guoying Zhang China Academy of Telecommunication Research of MII 11 Yue Tan Nan Jie Beijing, P.R.China Phone: +86-10-68094272 Email: zhangguoying@mail.ritt.com.cn Dan Li Huawei Technologies Co., Ltd. F3-5-B R&D Center, Huawei Base Bantian, Longgang District Shenzhen 518129 P.R.China Phone: +86-755-28973237 Email: danli@huawei.com Ming Chen European Research Center Huawei Technologies Zhang Expires September 2010 [Page 10] Internet-Draft OSPF Extensions for WSON March 2010 Riesstr. 25, 80992 Munchen, Germany Phone: 0049-89158834072 Email: minc@huawei.com Yabin Ye European Research Center Huawei Technologies Riesstr. 25, 80992 Munchen, Germany Phone: 0049-89158834074 Email: yabin.ye@huawei.com Acknowledgment We thank Ming Chen and Yabin Ye from DICONNET Project who provided valuable information for this document. Intellectual Property The IETF Trust 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 any IETF 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. Copies of Intellectual Property 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 any standard or specification contained in an IETF Document. Please address the information to the IETF at ietf-ipr@ietf.org. Zhang Expires September 2010 [Page 11] Internet-Draft OSPF Extensions for WSON March 2010 The definitive version of an IETF Document is that published by, or under the auspices of, the IETF. Versions of IETF Documents that are published by third parties, including those that are translated into other languages, should not be considered to be definitive versions of IETF Documents. The definitive version of these Legal Provisions is that published by, or under the auspices of, the IETF. Versions of these Legal Provisions that are published by third parties, including those that are translated into other languages, should not be considered to be definitive versions of these Legal Provisions. For the avoidance of doubt, each Contributor to the IETF Standards Process licenses each Contribution that he or she makes as part of the IETF Standards Process to the IETF Trust pursuant to the provisions of RFC 5378. No language to the contrary, or terms, conditions or rights that differ from or are inconsistent with the rights and licenses granted under RFC 5378, shall have any effect and shall be null and void, whether published or posted by such Contributor, or included with or in such Contribution. 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 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. Full Copyright Statement Copyright (c) 2010 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Zhang Expires September 2010 [Page 12]