REST versus SOAP as Architectural Style for Web Services

Representational State Transfer (REST) is a software architecture style for distributed systems such as the Internet first introduced by Fielding in his doctoral thesis in 2000. REST defines a set of principles defining how resources are defined and addressed in a networked environment. The most known implementation of REST is HTTP. REST advocates use of simple course grained operations (PUT, GET, POST and DELETE) to transport a resource across the network and then change the resources state locally by invocation of local accessible operations. This is in opposition to SOAP, where fine grained operations are accessed across the network in line with the Remote Procedure Call (RPC) programming model. The claim in this paper is that REST implemented as XML over HTTP is superior to SOAP as implementation strategy for networked services. On the other hand, we see the value of SOAP in Enterprise Application Integration scenarios involving middleware products such as Microsoft Biztalk and IBM WebSphere ESB.