Overview of web services and web service architectures. Web services have come of age and are the foundation of today's enterprise application architectures. Service Oriented Architecture (SOA) break up traditional application silos into reusable services shared and used by different applications. Web services group and encapsulate related functionality into reusable functional units. Web service intermediaries complement the business functionality exposed by web services with functions such as authentication, load balancing, logging and caching. To control web service consumer and producer compatibility, web services should carry the version of the service in the interface.