Review of State Based Approach Recovery Schemes in Mobile Distributed Environments

Fault tolerance techniques enable a system to perform tasks in the existence of faults. In a distributed system, hardware and software components are located at network computers and communication and coordination of their action is done by only passing messages. Mobile computing is progression of wireless network technology and portable information appliances such as laptops, handheld devices, PDAs etc. In the state based approach for recovery, known as snapshot, the entire state of a process is saved. When a recovery point is established, recovering a process involves reinstating its saved state and resuming the execution of the process from the state. Exhaustive research work has been carried out on designing efficient state based schemes for fault tolerance. In mobile distributed computing, due to mobility of MHs and limitations of wireless networks, there are new issues like mobility, catastrophic failure, limited battery life, low bandwidth, disconnections etc. That complicate the design of the snapshot algorithms. Recently, more attention has been given to providing state based approach of recovery for mobile systems. This paper surveys the algorithms reported in literature for introducing fault tolerance in mobile distributed systems and extension of it.