Mobility and Service Management for Future All-ip Based Wireless Networks

The next generation wireless network will provide not only voice but also data services. With the success of the Internet, it is widely believed that IP will become the foundation of next generation wireless networks. With the help of IETF standardization, IP-based wireless networks can benefit from existing and emerging IP related technologies and services. One key issue is how to provide uninterrupted, reliable and efficient data services to a mobile node (MN) in wireless networks. This dissertation concerns two major system-support mechanisms in future all-IP based wireless networks, namely, mobility management and service management. Mobility management addresses the issues of how to track and locate a mobile node efficiently. Service management addresses the issues of how to efficiently deliver services to mobile nodes. This dissertation aims to design and analyze integrated mobility and service management schemes for future all-IP based wireless systems. We propose and analyze peruser regional registration schemes for integrated mobility and service management with the goal to minimize the network signaling and packet delivery cost in future all-IP based wireless networks. We show that, when given a set of parameters characterizing the operational and workload conditions of a MN, there exists an optimal regional area size for the MN such that the network communication cost is minimized for serving mobility and service management operations of the MN. If access routers in future all-IP based wireless networks are restricted to perform network layer functions only, we investigate the design of intelligent routers, called dynamic mobility anchor points (DMAPs), to implement per-user regional management in IP wireless networks. These DMAPs are access routers (ARs) chosen by individual MNs to act as a regional router to reduce the signaling overhead for intra-regional movements. The DMAP domain size, i.e., the number of subnets covered by a DMAP, is based on a MN’s mobility and service characteristics. A MN optimally determines when and where to launch a DMAP to minimize the network cost in serving the user’s mobility and service management operations. We show that there exists an optimal DMAP domain size for each individual MN. If access routers are powerful and flexible in future all-IP based to perform networklayer and application-layer functions, we propose the use of per-user proxies that can run on access routers. The user proxies can carry service context information such as cached data items and Web processing objects, and perform context-aware functions such as content adaptation for services engaged by the MN to help application executions. Under the proxybased regional management scheme, a client-side proxy is created on a per-user basis to serve as a gateway between a MN and all services engaged by the MN. Leveraging Mobile IP with route optimization, the proxy runs on a foreign agent/access router and cooperates with the home agent and foreign agent/access router of the MN to maintain the location information of the MN, in order to facilitate data delivery by services engaged by the MN. Further, the proxy optimally determines when to move with the MN so as to minimize the network cost associated with the user’s mobility and service management operations. The proxy-based scheme supports query processing mobile applications. To improve query performance, the MN stores frequently used data in its cache. The MN’s proxy receives invalidation reports or updated data objects from application servers, i.e., corresponding nodes (CN) for cached data objects stored in the MN. If the MN is connected, the proxy will forward invalidation reports or fresh data objects to the MN. If the MN is disconnected, the proxy will store the invalidation reports or fresh data objects, and, once the MN is reconnected, the proxy will forward the latest cache invalidation report or data objects to the MN. We show that there is an optimal ”service area” under which the overall cost including query processing cost and location management cost is minimized. We demonstrate that our proposed per-user regional management scheme outperforms basic Mobile IPv6, Mobile IPv6 Regional Registration, and Hierarchical Mobile IPv6 that do not consider integrated mobility and service management and that use static regional routers to server all MNs in the system. We will develop a simulation model based on ns2 to validate analytical results. We will also investigate mobile applications to which the proposed integrated mobility and service management scheme can be applied in Mobile IP systems.