Compositionality and Compatibility of Service Contracts

Service Oriented Architecture (SOA) is a way of reorganizing series of previously operational software applications and support infrastructure into an interconnected set of services, each accessible through standard interfaces and messaging protocols. Once all the elements of an enterprise architecture are in place, existing and future applications can access these services as necessary. This architectural approach is particularly applicable when multiple applicationsrunning on varied technologies and platforms need to communicate with each other. It promotes services that are distributed, heterogeneous, autonomous and open in nature. In this way, enterprises can mix and match services to perform business transactions with less programming effort.In recent times, Service Oriented Architecture is being employed in developing service based applications. While this is a welcome idea by a versed majority of developers and vendors in the software industry, a lot of issues are yet to be resolved. For instance, collaboration presumes a minimum level of mutual trust and where ever trust is not considered sufficient, contracts become the alternative mechanism to reduce risks. Therefore, the possibility has arisen to havea detailed contract specification and of course verification for these service contracts in order to ensure a more reliable and dependable application. Two different web services from two different platforms or from two different organizations should be able to inter-operate based on the agreed contract.Techniques and tools to handle service contracts or that support analysis, verification and validation is important. There should be a possibility to represent service contracts whether for intra/inter-organizational applications that allows for analysis, verification and validation. Our goal is to add a representation and support for the functional aspects of service contracts to the existing non-functional aspects. Further, we investigate how to analyze, verify and validate service contracts laying emphasis on the compositionality and compatibility of service contracts.