Checkpoint-recovery protocol for reliable mobile systems

Information systems consist of mobile stations and fixed stations. Mission critical applications are required to be executed fault-tolerantly in these systems. However, mobile stations support neither enough volume of storage and processing power nor enough capacity of battery to do reliable, long-term communications. Moreover, wireless channels are less reliable. Hence, the channels with the mobile stations are often disconnected. Therefore, it is difficult for multiple mobile stations to synchronously take checkpoints since the communication channels with the mobile stations may be disconnected even during taking the checkpoints. In this paper, we propose a novel hybrid checkpointing protocol where the mobile stations take asynchronously and the fixed ones take synchronously checkpoints. Reliable information systems including mobile stations can be realized by the hybrid checkpointing protocol