A Proxy-Based Integrated Cache Consistency and Mobility Management Scheme for Mobile IP Systems

In this paper, we investigate a proxy-based integrated cache consistency and mobility management scheme in mobile IP systems. Our scheme is based on a stateful strategy by which cache invalidation messages are asynchronously sent by the server to a mobile host (MH) whenever data objects cached at the MH have been updated. We use a per-user proxy to buffer invalidation messages to allow the MH to disconnect arbitrarily and to reduce the number of uplink requests when the MH is reconnected. Moreover, the MH´s proxy serves as a gateway foreign agent (GFA) as in the MIP Regional Registration protocol to keep track of the address of the MH in a region. The proxy migrates with the MH when the MH crosses a regional area. We identify the optimal regional area size under which the overall network traffic cost, due to cache consistency management, mobility management, and query requests/replies, is minimized. We demonstrate that the integrated cache consistency and mobility management scheme outperforms both no-proxy and/or no-cache schemes in Mobile IPv6 environments.