Structuring Distributed Systems for Recoverability and Crash Resistance

An object-oriented multilevel model of computation is used to discuss recoverability and crash resistance issues in distributed systems. Of particular importance are the issues that are raised when recoverability and crash resistance properties are desired from objects whose concrete representations are distributed over several nodes. The execution of a program at a node of the system can give rise to a hierarchy of processes executing various parts of the program at different nodes. Recoverability and crash resistance properties are needed to ensure that such a group of processes leave the system state consistent despite faults in the system.