SOAP is a matured and stabilized protocol with a number of standard specifications, and these specifications are simplifying and streamlining the development, deployment, management, governance, and composition of services. There are standardized markup languages to represent the interfaces of services. In order to be unambiguously understood, SOAP predominantly uses XML rather than HTTP to define message content. Web services description language (WSDL) can enforce the use of formal contracts between the service API and consumers. SOAP has a built-in WS-reliable messaging standard to increase service security during asynchronous execution and processing. SOAP has a built-in stateful operation capability for conversational state management.
As indicated in the preceding section, REST is easy to understand as it uses HTTP as the data transmission protocol and the...