Network Working Group T. Sanda Internet Draft T. Ue Expires: August 2004 Panasonic February 2004 Pre CRN discovery from proxy on candidate new path draft-sanda-nsis-mobility-qos-proxy-00.txt Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026 [1]. 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. Abstract This document proposes one method of pre CRN discovery by using proxies on candidate new paths, i.e. the paths which will be established when MN moves to a new networks. Pre CRN discovery is used for fast state installation. Conventions used in this document 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 [2]. Table of Contents 1. Introduction................................................2 2. Requirements of Fast State Installation.....................3 Sanda et al. Expires - August 2004 [Page 1] Internet-Draft February 2004 3. Proxies.....................................................3 4. Pre CRN Discovery...........................................4 4.1 Mobile Node.............................................5 4.2 Proxy sends DCRN_DISCOVERY..............................6 4.3 Intermediate QNEs belonging to the signaling path from proxy to CN.................................................6 4.4 Correspondent Node......................................7 4.5 Intermediate QNEs belonging to the signaling path from CN to proxy....................................................7 4.6 Proxy receives UCRN_DISCOVERY...........................8 5. Signaling messages for fast CRN discovery...................9 6. Security Considerations.....................................9 References.....................................................9 Author's Addresses............................................10 1. Introduction When a MN performs L3 level handover, it is desirable to establish new QoS paths before the MN starts sending/receiving packets in new subnetwork. Furthermore, as described in [3] as "Fast State Installation", it may be better to prepare new QoS paths before MN moves from old sub network. Fast state installation may be accomplished by interacting with some mobility protocols such as FMIP or CT/CARD. However, it is unclear NSIS can trigger, and be triggered by mobility protocols. Moreover, it is required that the QoS scheme MUST have provisions to accomplish its tasks even if one or more these mobility protocols are not used [4]. Therefore, some solutions without interacting with mobility protocols are necessary to carry out fast state installation. This document proposes one way to accomplish fast state installation. The proposed way can work even if network does not support mobility protocols such as FMIP and CARD. Assumptions and terminology definition in this document are: o MN is QNE which supports mobility specific functionalities (mQNE). o "Upstream data flow" is a data flow from MN to CN, and "downstream data flow" is a data flow from CN and MN. o On-path signaling o Definition of "UCRN" and "DCRN" is the same as [6] o Only optimized route case is discussed in this document although several routes are possible such as triangle route, tunnel between OAR and NAR established by FMIP, and so on. Sanda et al. Expires - August 2004 [Page 2] Internet-Draft February 2004 2. Requirements of Fast State Installation This section describes some requirements of fast state installation. It is difficult for MN to initiate RESERVE (create) message for new path when it is still in old subnetwork. Therefore NSIS proxy utilization will be necessary for fast state installation, as described in [3]. Some types of usages are possible, such as. 1. Preparation Proxy prepares to create new paths for the MN, e.g. discovering CRNs in advance (pre CRN discovery). 2. Installation Proxy initiates RESERVE message for creating new paths in behalf of MN after/without preparation. If installation without preparation is performed, CRN discovery and route selection should be carried out simultaneously with reservation process in this case. The following section describes how to perform pre CRN discovery. 3. Proxies It is desirable that either old (current) or candidate new adjacent mQNEs of MN acts as a proxy. An example of the former case is described in an appendix of [5]. Here we aim to consider the latter case, i.e. new adjacent mQNE acts as a proxy and prepares new path creation. If candidate NAR(s) has mQNE functionalities, the NAR(s) acts as a proxy. Sanda et al. Expires - August 2004 [Page 3] Internet-Draft February 2004 new adjacent mQNE +..+ +---+ +----+ .MN.---|NAR|---|mQNE|---...-------- +..+ +---+ +----+ | ^ | | | +--+ +---+ +-+ +----+ +----+ +--+ |MN|===|OAR|==|R|==|mQNE|==...==|mQNE|==...==|CN| +--+ +---+ +-+ +----+ +----+ +--+ old (current) adjacent mQNE === current path --- expected new path R: Router or NE (not QNE) Figure1: New and old adjacent mQNE It is possible that new adjacent mQNE for upstream is not the same as the mQNE for downstream. This case it is desirable that a pair of new adjacent mQNE for upstream and downstream acts as proxy. 4. Pre CRN Discovery The basic idea of pre CRN (both UCRN and DCRN) discovery is as follows. o MN sends current flow identifier and session identifier (for both upstream and downstream, or either) information to proxies. o Each proxy sends a DCRN_DISCOVERY to CN. A DCRN_DISCOVERY is NSLP signaling message and containing the flow identifier and session identifier received from the MN. o All intermediate QNEs, which belonging to the signaling path from the proxy to CN, check if any interface has resource reservation for the pair of flow identifier and session identifier for upstream. If exist, the QNE appends an IP address of the interface to DCRN_DISCOVERY. o On receipt of DCRN_DISCOVERY, CN sends a UCRN_DISCOVERY to the proxy. A UCRN_DISCOVERY is NSLP signaling message and containing the flow identifier and session identifier received from MN via DCRN_DISCOVERY. A UCRN_DISCOVERY also contains the information of IP addresses appended to DCRN_DISCOVERY Sanda et al. Expires - August 2004 [Page 4] Internet-Draft February 2004 o All intermediate QNEs, which belonging to the signaling path from CN to the proxy, check if any interface has resource reservation for the pair of flow identifier and session identifier for downstream. If exist, the QNE appends an IP address of the interface to UCRN_DISCOVERY. o From the information contained in UCRN_DISCOVERY, the proxy is able to know IP addresses of DCRN and UCRN. DCRN_DISCOVERY +-----+ +----+ +----+ +----+ | |--->|mQNE|--->|mQNE|--->| | | | +----+ +----+ | | |Proxy| | CN | | | +----+ +----+ | | | |<---|mQNE|<---|mQNE|<---| | +-----+ +----+ +----+ +----+ ^ PROXY_INIT | UCRN_DISCOVERY | +----+ | | | MN | | | +----+ | | PROXY_INIT | | PROXY_INIT V V Figure2: Basic idea of pre CRN discovery The detailed operations are described in the following sub- sections. 4.1 Mobile Node There are some ways for MN to perform proxy discovery, e.g. MN can have a table of mQNE information locally and find an appropriate proxies mQNE according to candidate APs information in new subnetwork. Another way is that MN sends the APs information in new subnetwork to, e.g. CARD server, and obtains proxies information. After the proxy discovery, MN sends the new proxy PROXY_INIT which contains, at least, current session identifier, flow Sanda et al. Expires - August 2004 [Page 5] Internet-Draft February 2004 identifier, QoS path direction (upstream, downstream, or bi- directional). PROXY_INIT may include new care-of address (NCoA) so that new proxy mQNE can perform resource reservation in advance as well as CRN discovery. NCoA can be configured by MN if MN and network support FMIP. Even if MN and network do not support FMIP, MN which has an AP-AR mapping table locally can configure NCoA as soon as it listens to AP's link layer address. This case MN should select an access router (AR) which can be a new proxy mQNE to perform duplicate address detection (DAD). 4.2 Proxy sends DCRN_DISCOVERY Each proxy receiving PROXY_INIT from MN starts preparing CRN discovery. The proxy sets the information of data stream direction, flow identifier(s) and session identifier(s) contained in PROXY_INIT to DCRN_DISCOVERY, and sends it toward CN. A DCRN_DISCOVERY is NSLP signaling. An IP address of CN is contained in flow identifier. However, the PROXY_INIT may contain CN's IP address separately in addition to the other information. 4.3 Intermediate QNEs belonging to the signaling path from proxy to CN Each QNE belonging to the signaling path from proxy to CN intercepts DCRN_DISCOVERY, and checks if any interface has resource reservation for the pair of flow identifier and session identifier for upstream. If one of interface has the reservation, the QNE appends IP address of the interface to DCRN_DISCOVERY. If DCRN_DISCOVERY does not contain a pair of flow identifier and session identifier for upstream, each QNE does not carry out this checking process. By this procedure, DCRN_DISCOVERY can gather the information of all overlapping interfaces belonging to current upstream QoS path (from MN to CN) and expected new upstream path (from proxy to CN) in order. Sanda et al. Expires - August 2004 [Page 6] Internet-Draft February 2004 current path =======================> IF1 IF2 +--+ +----+ +----+ +----+ +----+ +--+ |MN|>>>>|mQNE|>>>|mQNE|>>>|mQNE|>>>|mQNE|>>>>|CN| +--+ +----+ +----+ >+----+>>>+----+>>>>+--+ ^ ^ -----> ^ | +-----+ +----+ ^ | |Proxy|>>>>>|mQNE|>>>> | +-----+ +----+ | | ------------------- DCRN_DISCOVERY IF=Inteface to be appended to the message Figure3: current upstream path and DCRN_DISCOVERY 4.4 Correspondent Node When CN receives DCRN_DISCOVERY, the CN sets the information of data stream direction, flow identifier(s) and session identifier(s) contained in DCRN_DISCOVERY to UCRN_DISCOVERY, and sends it toward CN. A UCRN_DISCOVERY is NSLP signaling message. If DCRN_DISCOVERY contains a pair of flow identifier and session identifier for upstream, the CN also sets interfaces IP addresses appended by intermediate QNEs belonging to the signaling path from proxy to CN. 4.5 Intermediate QNEs belonging to the signaling path from CN to proxy Each QNE belonging to the signaling path from CN to proxy intercepts UCRN_DISCOVERY, and checks if any interface has resource reservation for the pair of flow identifier and session identifier for downstream. If one of interface has the reservation, the QNE appends IP address of the interface to UCRN_DISCOVERY. If UCRN_DISCOVERY does not contain a pair of flow identifier and session identifier for downstream, each QNE does not carry out this checking process. By this procedure, DCRN_DISCOVERY can gather the information of all overlapping interfaces belonging to current upstream QoS Sanda et al. Expires - August 2004 [Page 7] Internet-Draft February 2004 path (from MN to CN) and expected new upstream path (from proxy to CN) in order. current path <======================= IF4 IF3 +--+ +----+ +----+ +----+ +----+ +--+ |MN|<<<<|mQNE|<<<|mQNE|<<<|mQNE|<<<|mQNE|<<<<|CN| +--+ +----+ +----+ <+----+<<<+----+<<<<+--+ v v ------ v | +-----+ +----+ v | |Proxy|<<<<<|mQNE|<<<< | +-----+ +----+ | | <------------------ UCRN_DISCOVERY IF=Inteface to be appended to the message Figure4: current downstream path and UCRN_DISCOVERY 4.6 Proxy receives UCRN_DISCOVERY The proxy receiving UCRN_DISCOVERY from CN checks appended information in UCRN_DISCOVERY and decides CRN(s). The first interface IP address appended to DCRN_DISCOVERY (and set into UCRN_DISCOVERY) is DCRN, and the last interface IP address appended to UCRN_DISCOVERY is UCRN. collected by collected by DCRN_DISCOVERY UCRN_DISCOVERY <===============> <===============> +------+--------+--------+------+--------+--------+ |up- |IP addr.|IP addr.|down- |IP addr.|IP addr.| |stream| of IF1 | of IF2 |stream| of IF1 | of IF2 | +------+--------+--------+------+--------+--------+ ^ ^ | | DCRN UCRN Figure5: collected information and DCRN/UCRN Sanda et al. Expires - August 2004 [Page 8] UCRN/DCRN information can be used in several ways for new QoS path establishment. The proxy may send this information to MN so that MN can embed them in RESERVE message after handover. It is possible for the proxy to keep this information. In this case the proxy can start new QoS path establishment soon after handover without waiting for RESERVE message from MN. The proxy can also start new QoS path establishment before handover if the proxy obtains MN's NCoA in advance. Current QoS context can be obtained, for instance, from discovered UCRN/DCRN. For the purposes above, it is required for RESERVE message to include IP addresses of UCRN/DCRN. It is also required for UCRN to translate the RESERVE (create) message into RESERVE (update) message and vice versa for DCRN in order to avoid duplicate reservation of common QoS path (CN-UCRN/DCRN). 5. Signaling messages for fast CRN discovery A DCRN_DISCOVERY and UCRN_DISCOVERY may be extended existing QoS NSLP message, such as QUERY and its RESPONSE [7]. This case, proxy can obtain downstream path information simultaneously with CRN discovery. 6. Security Considerations Security issues are addressed in section 12 of [manyfolks] but they are not covering candidate proxies (mQNEs) which are described in this document. Proper security handling must be provided in candidate proxy discovery. It is also required to consider the issues caused by sending PROXY_INIT which includes session and flow identifiers from MN to candidate proxies, such as session/reservation ownership. Future draft will include these issues. References 1. Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996. 2. Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997 3 X. Fu, et al., "Mobility Issues in Next Steps in Signaling (NSIS)", Internet Draft (work in progress), draft-fu-nsis-mobility-01.txt, October 2003 Sanda et al. Expires - August 2004 [Page 1] Internet-Draft February 2004 4 H. Chaskar et al., "Requirements of a Quality of Service (QoS) Solution for Mobile IP", RFC3583, September 2003 5 S. Lee, et al., "Mobility Functions in the QoS-NSLP", Internet Draft (work in progress), draft-lee-nsis-mobility-nslp- 01.txt, October 2003 6 Roland Bless, et al., "Mobility and Internet Signaling Protocols", Internet Draft (work in progress), draft-manyfolks- signaling-protocol-mobility-00.txt, January 2004 7 Sven Van den Bosch (Editor), "NSLP for Quality-of-Service signaling", Internet Draft (work in progress), draft-ietf-nsis- qos-nslp-01.txt, October 2003 Author's Addresses Takako Sanda Panasonic (Matsushita Electric Industrial Co., Ltd.) 5-3, Hikarino-oka, Yokosuka City, Kanagawa 239-0847, Japan Phone: (+81) 46 840 5764 Email: sanda.takako@jp.panasonic.com Toyoki Ue Panasonic (Matsushita Electric Industrial Co., Ltd.) 5-3, Hikarino-oka, Yokosuka City, Kanagawa 239-0847, Japan Phone: (+81) 46 840 5816 Email: ue.toyoki@jp.panasonic.com Full Copyright Statement Copyright (C) The Internet Society (2003). All Rights Reserved. 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Expires - August 2004 [Page 10] Internet-Draft February 2004 This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS 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. Sanda et al. Expires - August 2004 [Page 11]