About Web services – PB Docs 2017

Web services allow you to use preexisting components (available on
the Internet or on a local network) instead of writing new business logic
to perform common tasks invoked by the applications that you develop. Web
services originated when the Simple Object Access Protocol (SOAP) was
introduced. SOAP leverages Extensible Markup Language (XML) and usually
employs Hypertext Transfer Protocol (HTTP) as the transport. Invoking Web
services through SOAP requires serialization and deserialization of
datatypes, and the building and parsing of SOAP messages.

Part of the value of Web services comes from the Web Services
Description Language (WSDL), which enables a service to be
self-describing. WSDL defines an XML grammar for describing Web services
as collections of communication endpoints capable of exchanging messages.
WSDL service definitions provide documentation for distributed systems and
serve as a recipe for automating the details involved in applications
communication.

With SOAP and WSDL, using third-party components is easier because
interfaces between applications become standardized across disparate
platforms.

PowerBuilder supports the following Web services standards: