Telecommunication Networks Group Design , Implementation and Performance of Multicast - Based Paging for IP Mobility

Originally, paging has been used in cellular networks to alert a mobile station of an incoming call within a paging area comprised of several cells. Today’s most popular usage of paging is the exchange of short messages. With growing importance of all-IP mobile networks it is expected that an IP paging service will prevail. This report studies the usage of paging in IP-based networks to search mobile hosts in order to find their current point-of attachment. It allows the mobile host to update the network less frequently and to provide the network with only approximate location information. The approach is contrary to the case where a mobile host registers each time a handover occurs and the network tracks the exact location of the mobile host. Clearly, there is a tradeoff between tracking and searching. In this report the utilization of IP multicast for paging in mobile access networks supporting micro-mobility is investigated. The paging service is intended to facilitate efficient mobility support, supplementing multicast-based micro-mobility which supports host mobility by means of locationindependent addressing and routing. The scheme is augmented by multicast-based paging to improve its efficiency and scalability. Hence, we propose a multicast-based paging architecture and protocol, highlight selected implementation issues and estimate the gain/costs of paging for mobility support in a performance evaluation.