ISIS WG Internet Draft Jean-PhilippeNetworking Working Group JP. Vasseur StefanoInternet-Draft S. Previdi Intended status: Standards Track Cisco Systems Document: draft-ietf-isis-link-attr-02.txtSystems, Inc Expires: AprilAugust 10, 2007 February 6, 2007 October 2006Definition of an IS-IS Link Attribute sub-TLV draft-ietf-isis-link-attr-02.txtdraft-ietf-isis-link-attr-03.txt Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts.Internet- Drafts. 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 August 10, 2007. Copyright Notice Copyright (C) The IETF Trust (2007). Abstract This document defines a sub-TLV called "Link-attributes" carried within the TLV 22 and used to flood some link characteristics. Conventions used in this documentRequirements Language 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 [RFC].RFC 2119 [RFC2119]. Table of contentsContents 1. Introduction ..................................................2. . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Link-attributes sub-TLV format ................................2. . . . . . . . . . . . . . . . 3 3. Interoperability with routers non supporting this capability ..3. . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Security considerations .......................................3 5.IANA considerations ...........................................3 6. Intellectual PropertyConsiderations ..........................3. . . . . . . . . . . . . . . . . . . . . . 4 5. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 4 7. Acknowledgments ...............................................4 8.References ....................................................4 8.1. . . . . . . . . . . . . . . . . . . . . . . . . . 4 7.1. Normative references .........................................4 8.2References . . . . . . . . . . . . . . . . . . . 4 7.2. Informative references .......................................4 9.References . . . . . . . . . . . . . . . . . . 5 Authors' Addresses ............................................4 Full. . . . . . . . . . . . . . . . . . . . . . . . 5 Intellectual Property and Copyright Statement .........................................5Statements . . . . . . . . . . 6 1. Introduction [IS-IS] specifies the IS-IS protocol (ISO 10589) with extensions to support IPv4 in [IS-IS-IP].[RFC1195]. A router advertises one or several Link State Protocol data units which are composed of variable length tuples called TLVs (Type-Length-Value). [IS-IS-TE][RFC3784] defines a set of new TLVs whose aims are to add more information about links characteristics, increase the range of IS-IS metrics and optimize the encoding of IS-IS prefixes. This document defines a new sub-TLV named "Link-attributes" carried within the extended IS reachability TLV (type 22) specified in [IS-IS-TE].[RFC3784]. 2. Link-attributes sub-TLV format The link-attribute sub-TLV is carried within the TLV 22 and has a format identical to the sub-TLV format used by the Traffic Engineering Extensions for IS-IS [IS-IS-TE]:([RFC3784]): 1 octet of sub-type, 1 octet of length of the value field of the sub-TLV followed by the value field,field - in this case, a 16 bit flags field. The Link-attribute sub-type is 19 (to be assigned by IANA) and has a length of 2 octets. This sub-TLV is OPTIONAL and MAYMUST appear at most once for a single IS neighbor. If a received LSP contains more than one Link-Attribute Sub-TLV, an implementation MAY decide to consider only the first encountered instance. The following bits are defined: Local Protection Available (0x01). When set, this indicates that the link is protected by means of some local protection mechanism (e.g [FRR]).[RFC4090]). Link excluded from local protection path (0x02). When set, this link SHOULD not be included in any computation of a repair path by any other router in the routing area. The triggers for setting up this bit are out of the scope of this document. 3. Interoperability with routers non supporting this capability A router not supporting the link-attribute sub-TLV MUSTwill just silently ignore this sub-TLV. 4. Security considerations No new security issues are raised in this document. 5.IANA considerationsConsiderations IANA will assign a new codepoint for the link-attribute sub-TLV defined in this document and carried within TLV 22. Suggested value is 19 (to be assigned by IANA). 6. Intellectual Property Considerations The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertainIANA is requested to create a registry for bit values inside the implementation or uselink-attributes sub-TLV. The initial contents of the technology described inthis document or the extentregistry will be: Value Name Reference ----- ---- --------- 0x1 Local Protection Available [This Document] 0x2 Link Excluded from Local Protection [This Document] Further values are to which any license under such rights might or might notbe available; nor does it represent that it has made any independent effort to identify any such rights. Information onallocated by the proceduresStandards Action process defined in [RFC2434], with respect to rightsEarly Allocation (defined in RFC documents can be found[RFC4020]) permitted. 5. Security Considerations Any new security issues raised by the procedures in BCP 78 and BCP 79. Copies of IPR disclosures made tothis document depend upon the IETF Secretariat and any assurances of licensesopportunity for LSPs to be made available, orsnooped and modified, the resultease/difficulty of which has not been altered. As the LSPs may now contain additional information regarding router capabilities, this new information would also become available to an attempt madeattacker. Specifications based on this mechanism need to obtain a general license or permission fordescribe the usesecurity considerations around the disclosure and modification of their information. Note that an integrity mechanism, such proprietary rights by implementers or users of this specification canas one defined in [RFC3567] should be obtainedapplied if there is high risk resulting 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 email@example.com. 7. Acknowledgmentsmodification of capability information. 6. Acknowledgements The authors would like to thank Mike Shand andShand, Les Ginsberg and Bill Fenner for their useful comments. 8.7. References 8.17.1. Normative references [RFC] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels," RFC 2119.References [IS-IS] "Intermediate System to Intermediate System Intra-Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", ISO 10589. [IS-IS-IP][RFC1195] Callon, R., RFC 1195,"Use of OSI IS-IS for routing in TCP/IP and dual environments", RFC 1195, December 1990. [IS-IS-TE][RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2434] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 2434, October 1998. [RFC3784] Smit, H. and T. Li, "IS-IS extensions"Intermediate System to Intermediate System (IS-IS) Extensions for traffic engineering",Traffic Engineering (TE)", RFC 3784, June 2004. [RFC4020] Kompella, K. and A. Zinin, "Early IANA Allocation of Standards Track Code Points", BCP 100, RFC 3784. 8.24020, February 2005. 7.2. Informative references [FRR] PingReferences [RFC3567] Li, T. and R. Atkinson, "Intermediate System to Intermediate System (IS-IS) Cryptographic Authentication", RFC 3567, July 2003. [RFC4090] Pan, et al,P., Swallow, G., and A. Atlas, "Fast Reroute Extensions to RSVP-TE for LSP Tunnels", RFC 4090, May 2005. 9.Authors' Addresses Jean-PhilippeJP Vasseur Cisco Systems, Inc.Inc 1414 Massachusetts Avenue Boxborough, MA 01719 USA Email: firstname.lastname@example.org Stefano Previdi Cisco Systems, Inc.Inc Via Del Serafico 200 Roma, 00142 - Roma ITALYItaly Email: email@example.com Full Copyright Statement Copyright (C) The Internet Society (2006).IETF Trust (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. 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 SOCIETYSOCIETY, 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. Intellectual Property 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 firstname.lastname@example.org. Acknowledgment Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA).