SOAP (formerly a backronym for Simple Object Access Protocol) is a messaging protocol specification for exchanging structured information in the implementation of web services. It uses XML for its message format, and relies on application layer protocols, most often Hypertext Transfer Protocol (HTTP), for message negotiation and transmission. The Web Services Description Language (WSDL) is often used to provide a machine readable form of SOAP-based web services. Some of the earlier 1EdTech service-based specifications, e.g. Learner Information Services (LIS), are WSDL/SOAP based.
