Network-based Localized Mobility Management BOF (netlmm) xxxxxx, November 1 at xxxx-xxxx ============================= CHAIRS: James Kempf Phil Roberts DESCRIPTION: There is considerable evidence that mobility for IP hosts can be more efficiently handled if mobility management is broken down into localized mobility management and global mobility management. Local mobility involves movements across some administratively and geographically contiguous set of subnets, while global mobility involves movements across broader administrative, geographical, and topological domains. Previous work in the IETF has focused on supporting localized mobility management for Mobile IP hosts, and the protocols developed have required host-side support at the IP layer. Recently in the IETF, new work on global mobility management approaches other than Mobile IP suggests that a localized mobility management approach decoupled from the global mobility management protocol might result in a more modular mobility management system design and therefore more longevity and an easier evolution path. In the WLAN infrastructure market, WLAN switches, which perform localized mobility management without any host involvement, have seen widespread deployment, indicating the technical feasibility and positive user acceptance of this approach. This suggests a possible design paradigm that could be used to accommodate global mobility management protocols of different types while reducing host software complexity and expanding the range of hosts that could be accommodated: a network-based, localized mobility protocol with no host software required specifically for localized mobility management and no requirement for a network interface to change IP address when it changes to a new router. The task of the NETLMM Working Group is to design a protocol solution for network-based localized mobility management. The network-based localized mobility management protocol will conform to the following framework. Mobility anchor points within the wired network maintain a collection of routes for individual hosts. The routes point to the access routers on which mobile hosts currently are located. Packets for the mobile host are routed to and from the hosts through the mobility anchor point. When a host moves from one access router to another, the access routers send a route update to the mobility anchor point. While some host involvement is necessary and expected for generic mobility functions such as movement detection and to inform the access router about host movement, no specific host to network protocol will be required for localized mobility management. The working group will develop a protocol between the access routers and mobility anchor points that minimally has the following functions: - Handles a new mobile host that powers on or moves from another localized mobility management domain, or an existing mobile host that shuts down without any notice (i.e. crashes), - Handles routing update when a mobile host moves from one access router to another within the localized mobility management domain, The necessity for additional protocol functions may arise during Working Group discussions, so this list should not be taken as final. The protocol will be independent of any particular global mobility management protocol, and it must work across multiple different kinds of wired and wireless backbone network link layer types. The protocol itself will be agnostic with respect to the last hop link layer protocol between the host and the access router. Adaptation of the protocol to different kinds of last hop link layers is accomplished through an interface on the access router common to all link layers under which specific link layer mechanisms (possibly together with authentication mechanisms) can provide a reliable handover indication and unique identity for the host. This will enable the access router to do a route update using NETLMM on behalf of the host. In addition to the NETLMM protocol document, the Working Group will produce an informational document that describes how existing and developing IETF standards for host to access router communication on the local link can be used to accomplish secure triggering of route update. This document will be informational only, because some link protocols are expected to provide their own mechanisms. The scope of the work is initially limited to IPv6, and is primarily for networks covering larger geographical regions such as multiple corporate campuses and metropolitian areas. The protocol will not attempt to hide handover between two separate interfaces on the host. Security will be defined for the protocol based on standard IETF security protocols, but should maintain configuration flexibility for varying deployment circumstances. The protocol will not define a new tunneling protocol but will reuse existing IP tunneling mechanisms if necessary. The NETLMM protocol will maintain compatibility with other IETF standards, both existing and developing, such as NEMO, DNS, DNA, and global mobility protocols such as Mobile IP. The Working Group has the following deliverables: - A problem statement document that clearly and succinctly describes the problem posed by localized mobility management and why a network-based approach is desirable, - A requirements and gap analysis that drills down in more detail on the required properties for a protocol solution and why existing IETF protocols are insufficient, - A protocol design for an interoperable, scalable network-based localized mobility management protocol between the access routers and the mobility anchor point, - A document describing how existing or developing IETF protocol standards can be used between the access router and the host to inform the access router about the arrival of a host, for use when the wireless link protocol does not provide support for this function. This document will also discuss the issue of secure host identification. Out of scope for the first design are: route optimization, inter-access router tunneling to optimize handover, mechanisms for handover between localized mobility management domains (other than standard global mobility management protocols), IPv4 support, and multiple mobility anchor points. During the design process, these enhancements will be kept in mind, but actual work to incorporate them or other enhancements will be deferred until after the initial design is complete and the working group recharters. Schedule -------- Nov. 2005 - IETF 64, Charter Working Group. Feb. 2006 - Working Group Last Call on Problem Statement and Requirements drafts. March 2006 - IETF 65, Discuss Last Call comments on Problem Statement and Requirements drafts. April 2006 - Submit Problem Statement and Requirements drafts to IESG for publication as Informational RFCs. June 2006 - Working Group Last Call on Protocol draft. Working Group Last Call on host to access router draft. Aug. 2006 - IETF 66, Discuss Last Call comments on Protocol draft. Nov. 2006 - IETF 67, Submit Protocol draft for publication as Proposed Standard. Submit host to access router draft as Informational. Dec. 2006 - Recharter to address enhancements Mailing List ------------ netlmm@ngnet.it https://vesuvio.ipv6.cselt.it/mailman/listinfo/netlmm to subscribe