A session management protocol for mobile computing

The ACTS AC034 OnTheMove project is in the process of developing a mobile middleware architecture, called mobile application support environment (MASE), to support mobile multimedia applications over heterogeneous networks. MASE is an intermediate middleware layer between the application layer and the underlying heterogeneous networks (wireless and wireline networks). Wireless communication is unreliable, and frequent disconnections are common compared to wireline networks. Existing protocol suites such as TCP/IP have not been designed to interwork with wireless networks. Once the wireless network connection is permanently dropped, the transport may abort its connection, and any process running at the application layer would be terminated due to loss of transport connections. For applications that exchange large amounts of data, the loss of transport connections means that the applications need to start from scratch. In this paper, we describe a session management (SM) protocol, which enables any application to resume operation once the transport as well as the wireless network connection is restored. The SM protocol entity is part of MASE so that any mobile application could use the session management services for reliable data transfer. The SM protocol was designed, specified, simulated and validated using the ITU-T specification and description language (SDL) and its support-tools.