Efficient checkpoint-based failure recovery techniques in mobile computing systems

Conventional distributed and domino effect-free failure recovery techniques are inappropriate for mobile computing systems because each mobile host is forced to take a new checkpoint (based on coordinated checkpointing). Otherwise, multiple local checkpoints may need to be stored in stable storage (based on communication-induced checkpointing). Hence, this investigation presents a novel domino effect-free failure recovery technique that combines the merits of the above two checkpointing technologies for mobile computing systems. The algorithm is a three-phase protocol that ensures a consistent checkpoint. The first phase uses a coordinated checkpointing protocol among mobile support stations. In the second phase, a communication-induced checkpointing protocol is used between each mobile support station and its mobile hosts. In the last phase, each mobile support station sends a checkpoint request to its mobile host which hasn't received any message from the mobile support station during the second phase. Numerical results are provided which compare the proposed algorithm with both a quasi-synchronous failure recovery algorithm and a hybrid checkpoint recovery algorithm for mobile computing systems. According to the comparison, our scheme outperforms other schemes in terms of checkpoint overhead. Moreover, the proposed algorithm has several merits: domino effect-free, nonblocking, twice the checkpoint size, and scalability.