A Low-Overhead Non-Block Check Pointing and Recovery Approach for Mobile Computing Environment

Check pointing/rollback-recovery strategy is used for providing fault-tolerance to distributed applications (Y.M. Wang, 1997; M. Singhal & N. G. Shivaratri, 1994; R. E. Strom and S. Yemini 1985; R. Koo & S. Toueg, 1987; S. Venkatesan et al.,1997; G. Cao & M. Singhal, 1998; D. Manivannan & M. Singhal, 1999). A checkpoint is a snapshot of the local state of a process, saved on local nonvolatile storage to survive process failures. A global checkpoint of an n-process distributed system consists of n checkpoints (local) such that each of these n checkpoints corresponds uniquely to one of the n processes. A global checkpoint M is defined as a consistent global checkpoint if no message is sent after a checkpoint of M and received before another checkpoint of M (Y.M. Wang, 1997). The checkpoints belonging to a consistent global checkpoint are called globally consistent checkpoints (GCCs). The set of such checkpoints is also known as recovery line.