INTERNET DRAFT Pat R. Calhoun Category: Standards Track Sun Microsystems, Inc. Title: draft-calhoun-mobileip-gre-ext-00.txt Tom Hiller Date: September 2000 Peter J. McCann Lucent Technologies Yingchun Xu 3Com Corporation GRE Extensions Status of this Memo This document is an individual contribution for consideration by the Mobile IP Working Group of the Internet Engineering Task Force. Comments should be submitted to the mobile- ip@standards.nortelnetworks.com mailing list. Distribution of this memo is unlimited. This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. 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. Copyright (C) The Internet Society 2000. All Rights Reserved. Abstract The GRE specification contains a Key field, which MAY contain a value Calhoun et al. expires February 2001 [Page 1] INTERNET DRAFT September 2000 that is used to identify a particular GRE "flow". This specification defines a new Mobile IP extensions that is used to exchange the value to be used in the GRE Key field. This specification also introduces a new extension, called the GRE Type extension, which is used during registration to signal the GRE type that will be used for the Mobile Node's session. This extension is deemed important in order to allow the Mobility Agents to setup the necessary protocol interfaces prior to receiving the mobile's traffic. Table of Contents 1.0 Introduction 1.1 Requirements language 1.2 Fast handoffs 2.0 GRE Key extension 3.0 GRE Type extension 4.0 Error Values 5.0 GRE Encapsulation 6.0 IANA Considerations 7.0 Security Considerations 8.0 References 9.0 Acknowledgements 10.0 Authors' Addresses 11.0 Full Copyright Statement Calhoun et al. expires February 2001 [Page 2] INTERNET DRAFT September 2000 1.0 Introduction The GRE specification contains a Key field, which MAY contain a value that is used to identify a particular GRE "flow". This specification defines a new Mobile IP extensions that is used to exchange the value to be used in the GRE Key field. This specification also introduces a new extension, called the GRE Type extension, which is used during registration to signal the GRE type that will be used for the Mobile Node's session. This extension is deemed important in order to allow the Mobility Agents to setup the necessary protocol interfaces prior to receiving the mobile's traffic. 1.1 Requirements language In this document, the key words "MAY", "MUST, "MUST NOT", "optional", "recommended", "SHOULD", and "SHOULD NOT", are to be interpreted as described in [2]. 2.0 GRE Key extension The GRE Key extension MAY be included in Registration Requests [1], and Regional Registration Requests [3] whose 'G' bit is enabled. The GRE Key extension is used to inform the recipient of the Mobile IP request of the value to be used in GRE's Key field. 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 | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Key Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type TBD (non-skippable) [1] Length 6 Reserved This field MUST be set to zero (0). Calhoun et al. expires February 2001 [Page 3] INTERNET DRAFT September 2000 Key Identifier This is a four octet value assigned in the Registration or Regional Registration Request, and inserted in every GRE frame (see Section 5). 3.0 GRE Type extension The GRE Type extension MAY be included in Registration Requests [1], and Regional Registration Requests [3] whose 'G' bit is enabled. The GRE Type extension is used to signal to the peer the type of traffic that will be sent from the Mobile Node encapsulated in GRE. Note that only one GRE Type extension MAY be present in a request. If the GRE Type is not supported by the receiver of the Registration or Regional Registration Request, it MUST return the appropriate Reply with the Code field set to PROTO_NOT_SUPPORTED (see Section 4). If the GRE Type extension was present in the Request, all traffic for the Mobile Node MUST be of the type specified in this extension. 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 | GRE Type | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type TBD (skippable) [1] Length 6 GRE Type The GRE protocol type, as defined in [4]. 4.0 Error Values The following table contains the name of Code [1] to be returned in a Registration and Regional Registration Replies, the value for the Code, and the section in which the error is first mentioned in this specification. Calhoun et al. expires February 2001 [Page 4] INTERNET DRAFT September 2000 Error Name Value Section of Document ---------------------- ----- ------------------- PROTO_NOT_SUPPORTED TBD 3.0 5.0 GRE Encapsulation When the Registration or Regional Registration Request has the 'G' bit enabled, contains the GRE Key extension, all GRE [4] encapsulated packets for the Mobile Node MUST include the value found in the extension within the GRE Key field [5]. The receiver of the GRE frame will use the Key field to identify the particular Mobility Binding. 6.0 IANA Considerations The GRE Key extension defined in Section 2 and the GRE Type extension are Mobile IP registration extension as defined in RFC 2002 [1] and extended in RFC 2356 [6]. IANA should assign a value of 131 for this purpose. The Code values defined in Section 4 are error codes as defined in RFC 2002 [1] and extended in RFC 2344 [7] and RFC 2356 [6]. 7.0 Security Considerations This specification does not introduce any new security considerations, beyond those described in [1]. 8.0 References [1] C. Perkins, Editor. "IP Mobility Support". RFC 2002. October 1996. [2] S. Bradner. "Key words for use in RFCs to Indicate Requirement Levels". BCP 14. RFC 2119. March 1997. [3] E. Gustafsson, A. Jonsson, C. Perkins. "Mobile IP Regional Registration", draft-ietf-mobileip-reg-tunnel-02.txt (work in progress), March 2000. [4] Farinacci, D., Li, T., Hanks, S., Meyer, D. and Traina, P., "Generic Routing Encapsulation (GRE)," RFC 2784, March 2000. [5] Gopal Dommety. "Key and Sequence Number Extensions to GRE". Calhoun et al. expires February 2001 [Page 5] INTERNET DRAFT September 2000 draft-dommety-gre-ext-04.txt, June 2000. (work in progress) [6] Montenegro, G. and V. Gupta, "Sun's SKIP Firewall Traversal for Mobile IP", RFC 2356, June 1998. [7] G. Montenegro. Reverse Tunneling for Mobile IP. Request for Comments (Proposed Standard) 2344, Internet Engineering Task Force, May 1998. 9.0 Acknowledgements The authors would like to thank the authors of draft-ietf-mobileip- 3Gwireless-ext-04.txt, given that some text from that Internet Draft was copied into this specification. 10.0 Authors' Addresses Questions about this memo can be directed to: Pat R. Calhoun Network and Security Research Center, Sun Labs Sun Microsystems, Inc. 15 Network Circle Menlo Park, California, 94025 USA Phone: +1 650 786 7733 Fax: +1 650 786 6445 E-mail: pcalhoun@eng.sun.com Gopal Dommety Cisco Systems 170 West Tasman Drive San Jose, CA 95134 Phone: +1 408 525 1404 E-mail: gdommety@cisco.com Calhoun et al. expires February 2001 [Page 6] INTERNET DRAFT September 2000 Tom Hiller Lucent Technologies Rm 2F-218 263 Shuman Blvd Naperville, IL 60566-7050 USA Phone: +1 630 979 7673 Fax: +1 630 979 7673 E-Mail: tom.hiller@lucent.com Peter J. McCann Lucent Technologies Rm 2Z-305 263 Shuman Blvd Naperville, IL 60566-7050 USA Phone: +1 630 713 9359 Fax: +1 630 713 4982 E-Mail: mccap@lucent.com Yingchun Xu 3Com Corporation 1800 West Central Road Mount Prospect, USA 60056 Phone: +1 847 342 6814 E-mail: Yingchun_Xu@3com.com 11.0 Full Copyright Statement Copyright (C) The Internet Society (2000). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this docu- ment itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of develop- ing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as Calhoun et al. expires February 2001 [Page 7] INTERNET DRAFT September 2000 required to translate it into languages other than English. The lim- ited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DIS- CLAIMS 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." Calhoun et al. expires February 2001 [Page 8]