Mobile IP Working Group Gopal Dommety INTERNET DRAFT Kent Leung October 1999 Cisco Systems Expires April 2000 Mobile IP Vendor/Organization-Specific Extensions draft-ietf-mobileip-vendor-ext-01.txt 1. Status of this Memo 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 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. 2. Abstract This draft proposes extensions that can be used as a vendor or organization-Specific Extensions. These extensions will facilitate organizations to make specific extensions as they see fit for research or deployment purposes. Dommety, Leung [Page 1] Internet Draft Mobile IP Vendor-Specific Extensions October 1999 3. Introduction Current specification of Mobile IP [1] does not allow for organizations and vendor to include organization/vendor-specific extensions in the Mobile IP messages. With the wide scale deployment of Mobile IP it is useful to have a vendor or organization-Specific Extension. This draft proposes an extension that can be used for making organization specific extensions. 4. Vendor/Organization Specific Extensions Two Vendor/Organization Specific Extensions are described, Critical (CVSE) and Normal (NVSE) Vendor/Organization Specific Extensions. The basic differences are between the Critical and Normal Extensions is that when the Critical extension is encountered but not recognized, the message containing the extension MUST be silently discarded. Whereas when a Normal Vendor/Organization Specific Extension is encountered and not recognized, the extension is ignored, but the rest of the Extensions and message data MUST still be processed. Another difference between the two is that Critical Vendor/Organization Extension has a length field of two bytes. 4.1. Critical Vendor/Organization Specific Extension (CVSE) The format of this extension is as shown below. 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 | Vendor/Org-ID +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Vendor/Org-ID (cont) | Opaque Data... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: Vendor/Organization Specific Extension Type TBD-1 (value should be in the range of 0-127) Length Length in bytes of this extension, not including the Type and Length bytes. Vendor-ID The high-order octet is 0 and the low-order 3 octets Dommety, Leung [Page 2] Internet Draft Mobile IP Vendor-Specific Extensions October 1999 are the SMI Network Management Private Enterprise Code of the Vendor in network byte order, as defined in the Assigned Numbers RFC [2]. Opaque Data Vendor/organization specific data. These data fields may be published in future RFCs. The opaque data is zero or more octets. The actual format of the opaque data is site or application specific, and a robust implementation SHOULD support the field as undistinguished octets. The codification of the range of allowed usage of this field is outside the scope of this specification. It is recommended that opaque data be encoded as a sequence of vendor type/vendor length/value fields. The length field of this extension is chosen to be two bytes long to allow for more than 251 bytes of Opaque Data. If an implementation does not recognize the CVSE, according to RFC [1] the entire packet is to be silently dropped. But if an agent recognizes the CVSE, then it is aware of how to deal with the length size. 4.2. Normal Vendor/Organization Specific Extension (NVSE) The format of this extension is as shown below. 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 | Vendor/Org-ID +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Vendor/Org-ID (cont) | Opaque Data... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: Vendor/Organization Specific Extension Type TBD-2 (value should be in the range of 128-255) Length Length in bytes of this extension, not including the Type and Length bytes. Vendor-ID The high-order octet is 0 and the low-order 3 octets are the SMI Network Management Private Enterprise Code of the Vendor in network byte order, as defined in the Assigned Numbers RFC [2]. Opaque Data Vendor/organization specific data. These data fields may be publicized in future RFCs. The opaque data is zero or more octets. 4.3 Vendor/Organization Specific Extensions Processing Considerations When a Mobile IP agent receives registration request with an extension of type TBD-1 (CVSE) and recognizes it, but the extension contains an unknown/unsupported vendor ID or does not know how to interpret the opaque data or a part of opaque data, a registration reject MUST be sent with the error code to indicate that the registration was rejected due to the presence of an unknown CVSE. When a Mobile IP entity receives registration reply with an extension of type TBD-1 (CVSE) and recognizes it, but the extensions contains an unknown/unsupported vendor ID or does not know how to interpret the opaque data or a part of opaque data, the packet is silently discarded. When a Mobile IP entity receives registration request with an extension of type TBD-2 (NVSE) and recognizes it, but the extensions contains an unknown/unsupported vendor ID or does not know how to interpret the opaque data or a part of opaque data, that particular extension is skipped. NOTE that according to RFC [1], when an extension numbered within the range 0 through 127 is encountered but not recognized, the message containing that extension MUST be silently discarded. This draft is compliant with the above specification and specifies the action if the TBD-1 type is encountered and recognized, but does not support the vendor ID or the the vendor type extension within. 4.4 Error Codes The following error codes will be used. Registration denied by the Foreign agent: TDB-code1: Unsupported Vendor-ID or unable to interpret Opaque Data in the CVSE sent by the Mobile Node to the Foreign Agent. Registration denied by the Home agent: TDB-code2: Unsupported Vendor-ID or unable to interpret Opaque Data in the CVSE sent by the Mobile Node to the Home Agent. TDB-Code3: Unsupported Vendor-ID or unable to interpret Opaque Data in the CVSE sent by the Foreign Agent to the Home Agent. Dommety, Leung [Page 3] Internet Draft Mobile IP Vendor-Specific Extensions October 1999 5. Restrictions Multiple TLV's with the TBD-1 and TBD-2 types can be included in a message. TLVs with TBD-1 and TBD-2 types can be placed anywhere after the fixed portion of the Mobile IP message. These TLVs are expected to be protected by the corresponding authenticator as necessary. Ordering of these TLV's should not be modified by intermediate nodes. 6. Security Considerations This document assumes that the Mobile IP messages are authenticated using a method defined by the Mobile IP protocol. This proposal does not impose any additional requirements on Mobile IP messages from a security point of view. So this is not expected to be a security issue. 7. IPv6 Considerations This extension can be used in IPv4 and IPv6 alike. 8. Acknowledgments The authors would like to thank TR45.4 WG, TR45.6 WG, Jouni Malinen, and Patrice Calhoun for their useful discussions. 9. References [1] C. Perkins, Editor. IP Mobility Support. RFC 2002, October 1996. [2] Reynolds, J., and J. Postel, "Assigned Numbers", STD 2, RFC 1700, USC/Information Sciences Institute, October 1994. Dommety, Leung [Page 4] Internet Draft Mobile IP Vendor-Specific Extensions October 1999 10. Author Information Gopal Dommety Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134 e-mail: gdommety@cisco.com Kent Leung Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134 e-mail: kleung@cisco.com Dommety, Leung