autoconf Working Group Jaehwoon Lee Internet Draft Dongguk University Expires: April 29, 2009 Sanghynn Ahn University of Seoul Younghan Kim Soongsil University Yuseon Kim Sangeon Kim KT October 30, 2008 Scope-Extended Router Advertisement for Connected MANETs draft-jaehwoon-autoconf-sera-01.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 April 29, 2009. Copyright Notice Copyright (C) The IETF Trust (2008). Jaehwoon Lee, et al. Expires April 29, 2009 [Page 1] Internet-Draft Scope-Extended Router Advertisement Oct. 30, 2008 Abstract In the connected MANET, the MANET Border Router (MBR) is used to connect the MANET with the external network and MANET nodes are required to know the MBR address to communicate with hosts in the external network. One way of acquiring the MBR address is to use the Router Advertisement (RA) and the Router Solicitation (RS) messages. In order to allow RA/RS messages to be delivered in the multi-hop MANET, the modified RA/RS message has been defined [4]. However, this approach may incur the duplicate packet reception problem due to rebroadcasting of received RA/RS messages to its neighbors. In this draft, we define the scope-extended Router Advertisement/ Solicitation message for announcing/solicitating the MBR address in the connected MANET. In the scope-extended RA/RS message, a new message field, the sequence number field, is defined so that duplicate RA/RS messages can be detected based on the sequence number and the MBR address included in the message. Table of Contents 1. Introduction..................................................3 2. Terminology...................................................3 3. Message Format................................................4 3.1 IPv4......................................................4 3.1.1 ICMP Scope-Extended Router Solicitation Message.....4 3.1.2 ICMP Scope-Extended Router Advertisement Message....5 3.2 IPv6......................................................6 3.2.1 ICMP Scope-Extended Router Solicitation Message.....6 3.2.2 ICMP Scope-Extended Router Advertisement Message....8 3.3 Source Manet Address Option...............................9 4. Security Considerations.......................................9 5. IANA Considerations...........................................10 References.......................................................10 Author's Addresses...............................................10 Intellectual Property and Copyright Statements ..................12 Jaehwoon Lee, et al. Expires April 29, 2009 [Page 2] Internet-Draft Scope-Extended Router Advertisement Oct. 30, 2008 1. Introduction The mobile ad hoc network (MANET) enabls mobile nodes to communicate cia multiple wireless hops without the need of any wired infrastructure[1]. in a MANET, two nodes not within their transmission range have to deliver data to each other through other intermediate nodes. For forwarding packets destined to other nodes, each node mush have the routing capability, i.e., the mechanism for establishing data delivery routes between any pair of source and destination nodes, as well as acting as a source and/or a destination node(s). In addition to that, the IP address auto-configuration mechanism suitable for the MANET environment is required. The MANET ca be classified into the autonomous MANET and the subordinate MANET. For the subordinate MANET, the MANET Border Router (MBR) which acts as the gateway connecting the MANET with the Internet has been defined. Through the MBR, MANET nodes can communicate with hosts located in the Internet. Therefore, MANET nodes have to know the MBR address. Moreover IP address assigned to the MANET node should be suitable to the Internet topology. In other words, nodes within the MANET should have the IP address with the same network prefix. One way of obtaing the MBR address and network prefix is to use the Router Advertisement (RA) and Router Solicitation (RS) messages[2-3]. However, there RA and RS messages are delivered only upto 1 hop, so can not be used in a multi-hop wireless networks such as the MANET. In order to overcome this limitation, the modified RA message has been defined for the multi-hop wireless MANET[4]. However, in this approach, the duplicate packet reception problem can occur since, if a node broadcasts a RA/RS message, it can receive the same RA/RS message which was re-broadcasted by one of its neighbors. In this draft, we define the scope-extended Router Advertisement/ Solicitation message for announcing/solicitating the MBR address in the connected MANET. In the scope-extended RA/RS message, a new message field, the sequence number field, is defined so that duplicate RA/RS messages can be detected based on the sequence number and the IP address included in the message. 2. Terminology No new terminology is defined in this draft. Jaehwoon Lee, et al. Expires April 29, 2009 [Page 3] Internet-Draft Scope-Extended Router Advertisement Oct. 30, 2008 3. Message Format 3.1 IPv4 In IPv4, the scope-extended router solicitation/advertisement information is included in the ICMP message [2]. 3.1.1 ICMP Scope-Extended Router Solicitation Message 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 | Code | Checksum | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Sequence Number| Cur hop limit | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Originator Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IP Fields: Source Address The IP address configured at the MANET interface of the MANET router (MR) sending this message. Destination Address 224.0.0.1 or 255.255.255.255 Time-to-Live 1 ICMP Fields: Type TBD Code 0 Sequence Number This number is increased by 1 whenever the originating MR sends a scope-extended RS message. The sequence number and the originator address (see below) are used for the message duplication check. Jaehwoon Lee, et al. Expires April 29, 2009 [Page 4] Internet-Draft Scope-Extended Router Advertisement Oct. 30, 2008 Cur Hop Limit Initially set to 255. An intermediate route reduces this value by 1 before rebroadcasting it. If the reduced value is 0, this message is silently discarded. Reserved Sent as 0; ignored on reception. Originator Address The IP address assigned to the MANET interface of the MR that originates the message. 3.1.2 ICMP Scope-Extended Router Advertisement Message 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 | Code | Checksum | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Sequence Number| Cur Hop Limit | Prefix Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | Lifetime | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | MBR Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IP Fields: Source Address The IP address configured at the MANET interface of the MR sending this message. If this message is sent as a reply to a scope-extended RS message, this field has the IP address configured at the MANET interface of the MBR originating this scope-extended RA message. If it is a proactively sent message, this field has the IP address configured at the MANET interface of the MR sending this message. Destination Address The IP address of the MANET interface of the MR originating the scope-extended RS message, if this scope-extended RA message is sent as a reply to the scope-extended RS message. Otherwise, set to the broadcast address. Jaehwoon Lee, et al. Expires April 29, 2009 [Page 5] Internet-Draft Scope-Extended Router Advertisement Oct. 30, 2008 Time-to-Live 1 if the Destination Address is the broadcast address; at least 1, otherwise. ICMP Fields: Type TBD Code 0 Sequence Number If this message is sent as a reply to a scope-extended RS message, this field is set to the Sequence Number in the scope- extended RS message. Otherwise, i.e., if this message is sent proactively, the value of this field is increased by 1 by the MBR. The sequence number and the MBR address are used for the message duplication check. Cur hop limit Initially set to 255. An intermediate route reduces this value by 1 before rebroadcasting it. If the reduced value is 0, this message is silently discarded. Prefix Length The prefix length of the IPv4 address assigned to the MANET interface of the MBR. MBR Address The IP address assigned to the MANET inter- face of the MBR originating this message. 3.2 IPv6 In IPv6, the scope-extended router solicitation/advertisement information is defined as a part of the neighbor discovery in [3]. 3.2.1 ICMP Scope-Extended Router Solicitation Message Jaehwoon Lee, et al. Expires April 29, 2009 [Page 6] Internet-Draft Scope-Extended Router Advertisement Oct. 30, 2008 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 | Code | Checksum | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Sequence Number| Cur Hop Limit | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | Originator Address | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IP Fields: Source Address The IP address configured at the MANET interface of the MR sending this message. Destination Address The all-routers multicast address or the all-nodes multicast address. Time-to-Live 1 ICMP Fields: Type TBD Code 0 Sequence Number This number is increased by 1 whenever the originating MR sends a RS message. The sequence number and the originator address are used for the message duplication check. Cur Hop Limit Initially set to 255. An intermediate route reduces this value by 1 before rebroadcasting it. If the reduced value is 0, this message is silently discarded. Originator Address The IP address assigned to the MANET interface of the MR originating the message. 3.2.2 ICMP Scope-Extended Router Advertisement Message Jaehwoon Lee, et al. Expires April 29, 2009 [Page 7] Internet-Draft Scope-Extended Router Advertisement Oct. 30, 2008 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 | Code | Checksum | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Sequence Number| Prefix Length | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Cur Hop Limit |M|O| Reserved | Router Lifetime | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reachable Time | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Retrans Timer | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | MBR Address | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IP Fields: Source Address If this message is sent as a reply to a scope-extended RS message, this field has the IP address configured at the MANET interface of the MBR originating this message. If this messages is a proactively sent message, this field has the IP address configured at the MANET interface of the MR sending this message. Destination Address Typically the Source Address of the invoking scope-extended Router Solicitation or the all-nodes multicast address. Hop Limit 1 if the Destination Address is the all-routers multicast address or the all-nodes multicast address; at least 1, otherwise. ICMP Fields: Type TBD Code 0 Jaehwoon Lee, et al. Expires April 29, 2009 [Page 8] Internet-Draft Scope-Extended Router Advertisement Oct. 30, 2008 Sequence Number If this message is sent as a reply to a scope-extended RS message, this field is set to the Sequence Number in the scope- extended RS message. Otherwise, i.e., if this message is sent proactively, the value of this field is increased by 1 by the MBR. The sequence number and the MBR address are used for the message duplication check. Prefix Length The prefix length of the IPv6 address assigned to the MANET interface of the MBR. Cur Hop Limit Initially set to 255. An intermediate route reduces this value by 1 before rebroadcasting it. If the reduced value is 0, this message is silently discarded. MBR Address The IPv6 address configured at the MANET interface of the MBR originating this message. 4. Security Consideration There is no special security considerations in this draft. 5. IANA Considerations This draft document defines a new type in the ICMP message. An Type value for the scope-extended Router Discovery message for MANET must be assigned by IANA. References [1] E. Baccelli, "Address Autoconfiguration for MANET: Terminology and Problem Statement", draft-ietf-autoconf-statement-04, Work in progress, Feb. 2008. [2] S. Deering, "ICMP Router Discovery Messages", RFC 1256, Sep. 1991. Jaehwoon Lee, et al. Expires April 29, 2009 [Page 9] Internet-Draft Scope-Extended Router Advertisement Oct. 30, 2008 [3] T. Narten, E. Nordmark, W. Simpson and H. Soliman, "Neighbor Discovery for IP version 6 (IPv6)", RFC 3861, Sep. 2007. [4] R. Wakikawa, J. Malinen, C. Perkins, A. NIlsson and A. Tuominen, Global connectivity for IPv6 Mobile Ad Hoc Networks", Work in progress, Oct. 2003. Author's Addresses Jaehwoon Lee Dongguk University 26, 3-ga Pil-dong, Chung-gu Seoul 100-715, KOREA Email: jaehwoon@dongguk.edu Sanghyun Ahn University of Seoul 90, Cheonnong-dong, Tongdaemun-gu Seoul 130-743, KOREA Email: ahn@uos.ac.kr Younghan Kim Soongsil University 11F Hyungnam Engineering Bldg. 317, Sangdo-Dong, Dongjak-Gu, Seoul 156-743 Korea E-main: yhkim@dcn.ssu.ac.kr Yuseon Kim KT 17 Woomyeon-dong, Seocho-gu Seoul 137-792, KOREA Email: yseonkim@kt.co.kr Sangeon Kim KT 17 Woomyeon-dong, Seocho-gu Seoul 137-792, KOREA Email: sekim@kt.co.kr Jaehwoon Lee, et al. Expires April 29, 2009 [Page 10] Internet-Draft Scope-Extended Router Advertisement Oct. 30, 2008 Full Copyright Statement Copyright (C) The IETF Trust (2008). 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 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 HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. 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