Network Working Group S. Daniel Park Internet-Draft SAMSUNG Electronics Expires: March 10, 2007 Y. Ohba Toshiba J. Jee ETRI September 9, 2006 DHCP Option for Discovering IEEE 802.21 Information draft-daniel-dhc-mihis-opt-02.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 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 March 10, 2007. Copyright Notice Copyright (C) The Internet Society (2006). All Rights Reserved. Abstract In IEEE 802 Standard, the Media Independent Handover (MIH) Services are under work through IEEE 802.21 Working Group. It is consist of three services, Media Independent Event Service (MIES), Media Independent Command Service (MICS) and Media Independent Information Service (MIIS). This document provides a mechanism by which the DHCP can provide information about the MIIS Discovery Information. Park, et al. Expires March 10, 2007 [Page 1] Internet-Draft DHCP Option for IEEE 802.21 September 2006 1. Introduction In IEEE 802 Standard, the Media Independent Handover Services are under work through IEEE 802.21 Working Group. It is consist of three services, Media Independent Event Service (MIES), Media Independent Command Service (MICS) and Media Independent Information Service (MIIS). MIIS provides a framework by which a MIH function both in the mobile node and in the network can discover and obtain homogeneous and heterogeneous network information within a geographical area to facilitate handovers. In the larger scope, the macro objective is to acquire a global view of the heterogeneous networks to facilitate seamless handovers when roaming across these networks. MIIS includes support for various Information Elements (IEs) stored in Information Server (IS). IEs provide information that is essential for a handover module to make intelligent handover decision. Figure 1 gives a high level description of scenario that distinguish between two different types of mobility as Horizontal Handovers and Vertical Handovers. Media Specific Media Independent Information Service Technology +------------+ +----------------------------------+ | | ^ | | | +--------+ | | | +-------+ +--------+ | | | GSM | | | | | BSTN 1| . . . . | BSTN x | | | +--------+ | V | +-------+ +--------+ | | . | e | . | | . | r | . | | . | t | +-------+ +-------+ | | +--------+ | i | | BS 1 | . . . . | BS y | | | | 802.16 | | c | +-------+ +-------+ | | +--------+ | a | | | | l | ------------+-----+ | | | / /-----| GNI | | +--------+ | H | +------+ +------+ +------+ | +-----+ | | 802.11 | | O | | AP 1 | | AP 2 | . . | AP z | | | LLI | | +--------+ | s | +------+ +------+ +------+ | +-----+ | | | | | | HLSI| +------------+ +----------------------------------+ +-----+ ---Horizontal HOs----------------> Park, et al. Expires March 10, 2007 [Page 2] Internet-Draft DHCP Option for IEEE 802.21 September 2006 Depending on the type of mobility support for different types of information elements may be necessary for performing handovers. MIIS provides the capability for obtaining the necessary information for handovers. This includes information about lower layers such as neighbor maps and other link layer parameters as well as information about available higher layer services such as access to internet connectivity, availability of VPN services, etc. The set of different higher services privided by the MIIS may constantly evolve. At the same time, the list of access networks that are supported by MIIS may also evolve. A schema defines structure of information. A schema is used in the 802.21 information service to define the structure of each information element as well as the relationship among different information elements supported. A schema is defined by a language and may be represented in multiple ways. Examples include Resource Description Framework (RDF) which is based on XML which is used in 802 MIBs, Variants or a simple TLV representation of different information elements. The MIIS schema is classified into two major categories. - Basic schema that is essential for every MIH to support and - Extended schema that is optional and can be vendor specific Note: further details are described in [ieee80221]. This document defines new DHCPv4[RFC2131] and DHCPv6 [RFC3315] options as MIIS Discovery Option for discovering MIIS Information. 2. Requirements 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 [RFC2119]. 3. MIIS Discovery Information The following information is defined as MIIS Discovery Information. o A list of IP addresses of MIIS Information Servers. This information is used by an MIIS client on a host to communicate with MIIS Information Servers using an MIIS transport protocol. (Note: an Park, et al. Expires March 10, 2007 [Page 3] Internet-Draft DHCP Option for IEEE 802.21 September 2006 MIIS transport protocol is being defined in MIPSHOP WG) o An URL of an extended schema. This information is used by an MIIS client on a host to obtain an extended schema that is located at a specified URL. The extended schema may be stored in a node that is not acting as an MIIS Information Server. The MIIS client needs to know the URL of the extended schema regardless of whether the extended schema is stored in an MIIS Information Server or not. o An DHCP option for a schema URL is needed for an extended schema only. for the basic schema, an IANA-assigned persistent URL will be used and the URL is supposed to be pre-configured in an MIIS client on a host, thus an DHCP option for a basic schema URL is not needed. 4. MIIS Discovery Option This option specifies the MIIS Discovery Information that client should use when discovering the handover information of MIIS somehow via the Dynamic Host Configuration Protocol [RFC2131]. 4.1 MIIS Information Server IPv4 Address Option for DHCPv4 The DHCPv4 format of the MIIS Information Server IPv4 Address Option is shown as follows; 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | option-code | option-length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | +Information Server IPv4 Address+ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The option-code for this option is TBD. The length of this option MUST be a multiple of 4. Information Server IPv4 Address field contains an IPv4 address of a MIIS Information Server. In a single Information Server IPv4 Address case, the length is 4. if multiple addresses are in use, the Information Servers are listed in the order of preference. Park, et al. Expires March 10, 2007 [Page 4] Internet-Draft DHCP Option for IEEE 802.21 September 2006 A DHCPv4 client requests the MIIS Information Server IPv4 Address Option in a Parameter Request List as described in [RFC2131] and [RFC2132]. The DHCPv4 client MUST try the records in the order listed in the MIIS Information Server IPv4 Address option. 4.2 MIIS Extended Schema URL Option for DHCPv4 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | option-code | option-length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + MIIS Extended Schema URL + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The option-code for this option is TBD. The length of this option is variable. MIIS Extended Schema URL field contains one URL of IEEE 802.21 Information Service Schema where the resource represented by the URL is an Extended Schema [ieee80221]. The length of option is variable. A DHCPv4 client requests the MIIS Extended Schema URL Option in a Parameter Request List as described in [RFC2131] and [RFC2132]. 4.3 MIIS Information Server IPv6 Address Option for DHCPv6 The DHCPv6 format of the MIIS Information Server IPv6 Address Option is shown as follows; Park, et al. Expires March 10, 2007 [Page 5] Internet-Draft DHCP Option for IEEE 802.21 September 2006 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 2 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | option-code | option-length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | Information Server IPv6 Address | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The option-code for this option is TBD. The length of this option MUST be a multiple of 16. Information Server IPv6 Address field contains an IPv6 address of a Information Server. In a single Information Server IPv6 Address case, the length is 16. if multiple addresses are in use, the Information Servers are listed in the order of preference. A DHCPv6 client requests the MIIS Information Server IPv6 Address Option in an Option Request Option as described in [RFC3315]. The DHCPv6 client MUST try the records in the order listed in the MIIS Information Server IPv6 Address option. 4.4 MIIS Extended Schema URL Option for DHCPv6 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 2 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | option-code | option-length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + | MIIS Extended Schema URL | + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Park, et al. Expires March 10, 2007 [Page 6] Internet-Draft DHCP Option for IEEE 802.21 September 2006 The option-code for this option is TBD. The length of this option is variable. MIIS Extended Schema URL field contains one URL of IEEE 802.21 Information Service Schema where the resource represented by the URL is an Extended Schema [ieee80221]. The length of option is variable. A DHCPv6 client requests the MIIS Extended Schema URL Option in an Options Request Option as described in [RFC3315]. 5. Security Considerations A rogue DHCP server can issue invalid or incorrect MIIS Discovery Information. This may cause denial of service due to unreachability or makes the client to reach incorrect destination. In case of DHCPv4, the authenticated DHCP [RFC3118] can be also used for secure exchange between clients and MIIS Information Server locations. In case of DHCPv6, the security considerations are described in Section 23 of [RFC3315]. 6. IANA Considerations IANA is requested to assign values for the MIIS Discovery Option code - MIIS Information Server IPv4 Address Option for DHCPv4, MIIS Extended Schema URL Option for DHCPv4, MIIS Information Server IPv6 Address Option for DHCPv6, MIIS Extended Schema URL Option for DHCPv6 - in accordance with [RFC2939]. 7. Acknowledgements Thanks to IEEE 802.21 folks for their effort on this issue. Specially thanks to David Hankins for his valuable comments. 8. No I-D References All references cited in this section MUST be added into the Informative References before publishing it officially. [ieee80221] IEEE P802.21/D01/08, Draft IEEE standard for Local and Metropolitan Area Networks: Media Independent Handover Services. 9. References Park, et al. Expires March 10, 2007 [Page 7] Internet-Draft DHCP Option for IEEE 802.21 September 2006 9.1 Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2939] Droms, R., "Procedures and IANA Guidelines for Definition of New DHCP Options and Message Types", BCP 43, RFC 2939, September 2000. 9.2 Informative References [RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC 2131, March 1997. [RFC2132] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor Extensions", RFC 2132, March 1997. [RFC3118] Droms, R. and W. Arbaugh, "Authentication for DHCP Messages", RFC 3118, June 2001. [RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C. and M. Carney, "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", RFC 3315, July 2003. Authors' Addresses Soohong Daniel Park Mobile Convergence Laboratory, SAMSUNG Electronics EMail: soohong.park@samsung.com Yoshihiro Ohba Toshiba EMail: yohba@tari.toshiba.com Junghoon Jee ETRI EMail: jhjee@etri.re.kr Park, et al. Expires March 10, 2007 [Page 8] Internet-Draft DHCP Option for IEEE 802.21 September 2006 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. 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Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Park, et al. Expires March 10, 2007 [Page 9]