Termination detection protocols for mobile distributed systems

This paper studies a fundamental problem, the termination defection problem , in distributed systems. Under a wireless network environment, we show how to handle the host mobility and disconnection problems. in particular, whe n some distributed processes are temporarily disconnected, we show how to c apture a weakly terminated state where silence has been reached only by tho se currently connected processes. A user may desire to know such a state to tell whether the mobile distributed system is still running or is silent b ecause some processes are disconnected. Our protocol tries to exploit the n etwork hierarchy by combining two existing protocols together. It employs t he weight-throwing scheme [9], [16], [21] on the wired network side, and th e diffusion-based scheme [5], [13] on each wireless cell. Such a hybrid pro tocol can better pave the gaps of computation and communication capability between static and mobile hosts, thus more scalable to larger distributed s ystems. Analysis and simulation results are also presented.