Web Services
Web services are a new breed of Web application. They are self-contained, self-describing, modular applications thay can be published, located, and invoked across the web. Web services perform functions, which can be anything from simple requests to complicated business processes ... Once a web service is deployed, other applications (and other web services) can discover and invoke the deployed service
IBM Web Service Tutorial
Web services connect devices in new ways by using the internet to exchange data, the key to web services is on-the-fly software creation through the use of loosely coupled, reusable software components. This allows systems to be decentralised and distributed around the internet.
Web services are formed around the following attributes:
- Web-based Protocols, based on HTTP so they can traverse firewalls.
- Interoperability, by use of the SOAP (standard mechanism for sending XML over HTTP) common standard.
- XML Based, to create standardised machine-readable documents.
- UDDI (Universal Description, Discovery and Integration), a mechanism for clients to find web services by creating a platform independent framework for describing and discovering services.
- WSDL (Web Services Definition Language), a method to describe the syntax of invocation and response of a web service.