Web Services - Components

Over the past few years, three primary technologies have emerged as worldwide standards that make up the core of today's web services technology. These technologies are discussed below.


This is the simplest XML-based protocol for exchanging information between computers.

  • XML-RPC is a simple protocol that uses XML messages to perform RPCs.

  • Requests are encoded in XML and sent via HTTP POST.

  • XML responses are embedded in the body of the HTTP response.

  • XML-RPC is platform-independent.

  • XML-RPC allows diverse applications to communicate.

  • A Java client can speak XML-RPC to a Perl server.

  • XML-RPC is the easiest way to get started with web services.

To learn more about XML-RPC, visit our XML-RPC Tutorial.


SOAP is an XML-based protocol for exchanging information between computers.

  • SOAP is a communication protocol.

  • SOAP is for communication between applications.

  • SOAP is a format for sending messages.

  • SOAP is designed to communicate via Internet.

  • SOAP is platform independent.

  • SOAP is language independent.

  • SOAP is simple and extensible.

  • SOAP allows you to get around firewalls.

  • SOAP will be developed as a W3C standard.

To learn more about SOAP, visit our SOAP Tutorial.


WSDL is an XML-based language for describing web services and how to access them.

  • WSDL stands for Web Services Description Language.

  • WSDL was developed jointly by Microsoft and IBM.

  • WSDL is an XML based protocol for information exchange in decentralized and distributed environments.

  • WSDL is the standard format for describing a web service.

  • WSDL definition describes how to access a web service and what operations it will perform.

  • WSDL is a language for describing how to interface with XML-based services.

  • WSDL is an integral part of UDDI, an XML-based worldwide business registry.

  • WSDL is the language that UDDI uses.

  • WSDL is pronounced as 'wiz-dull' and spelled out as 'W-S-D-L'.

To learn more about WSDL, visit our WSDL Tutorial.


UDDI is an XML-based standard for describing, publishing, and finding web services.

  • UDDI stands for Universal Description, Discovery, and Integration.

  • UDDI is a specification for a distributed registry of web services.

  • UDDI is platform independent, open framework.

  • UDDI can communicate via SOAP, CORBA, and Java RMI Protocol.

  • UDDI uses WSDL to describe interfaces to web services.

  • UDDI is seen with SOAP and WSDL as one of the three foundation standards of web services.

  • UDDI is an open industry initiative enabling businesses to discover each other and define how they interact over the Internet.

To learn more about UDDI, visit our UDDI Tutorial.