A Protocol Description Language for Customizing Failure Semantics

To optimize performance in a fault-tolerant distributed system, it is often necessary to enforce different failure semantics for different components. By choosing a custom set of failure semantics for each component and then by enforcing the semantics with a minimal set of protocols for a particular architecture, performance may be maximized while ensuring the desired system behavior. We have developed DIL, a language for specifying, on a per-component basis, protocols that transparently enforce failure semantics. These protocols may be reused with arbitrary components, allowing the development of a library of protocols. 1 Introduction Although descriptions of dependability protocols in the literature are relatively simple and concise, incorporating the protocols into an application often requires custom routines which intermix code for the application with that of the protocol. Such intermixing significantly increases the complexity of the code. One way to avoid the resulting comple..