Verifying Properties of Distributed Systems: Prospects for Practicality

Industry is rapidly embracing distributed systems. Although there are many advantages to distribution, such systems are certainly more difficult to understand and thus more vulnerable to errors. Unfortunately, insufficient thought is being given to how to ensure the reliability of such systems. Whereas dynamic testing approaches provide increased confidence in the reliability of sequential systems, for distributed systems even the repeatability of a given test execution result cannot be counted upon. Alternative validation approaches, such as formal verification and static analysis, are usually complicated to use and often intractable. In this talk we describe a static analysis tool, called FLAVERS, that addresses these limitations and offers a promising approach for validating distributed systems.. FLAVERS was designed to be used by typical developers on real distributed software to prove important user-defined properties about the behavior of such systems. Industrial developers have been successful in applying FLAVERS to a diverse set of projects. But these successes also indicated hurdles that remain before FLAVERS, or similar techniques, can be expected to see wide acceptance. These hurdles, and our approaches for overcoming them, will be described in this talk.