Web Services is an application that exposes an API that can be called through the web. That is to say, you can call this application with a programming method. Web Services is a new platform for establishing interoperable distributed applications. Theweb Services platform is a standard that defines how the application implements interoperability on the Web. You can use any language you like, write Web Service on any of your favorite platform, just we can query and access these services through the Web Services standard.
From a deep level, Web Services is a new web application score, which is self-contained, self-description, modular applications, can be described in network (usually web), release, look, and through the Web Call. WebServices is a network-based, distributed modular component, which performs specific tasks, complies with specific technical specifications, which make Web Services interoperate with other compatible components. It can use standard Internet protocols, like hypertext transport protocols HTTP and XML, will be reflected in the Internet and enterprise online.
The Web Services platform requires a set of protocols to create a distributed application. Any platform has its data representation method and type system. To achieve interoperability, the Web Servi-CES platform must provide a set of standard type systems for communication with different types of systems in different platforms, programming languages, and component models. At present, these protocols are:
1.xml and XSD
Scalable Markup Language XML is a basic format that represents data in the Web Services platform. In addition to easy establishment and easy analysis, the main advantage of XML is that it has nothing to do with the platform and has nothing to do with the manufacturer. XML is created by the World Wide Web Association (W3C), and the XML SchemaxSD set by W3C defines a set of standard data types and gives a language to extend this set of data types. The Web Services platform is used as the data type system with XSD. When you construct a Web Services when you use some languages such as Java, in order to comply with the Web Services standard, all the data types you use must be converted to the XSD class.
2.soap
SOAP is a Simple Object Access Protocol, which is a lightweight protocol used to exchange XML encoded information. It has three main aspects: XML- Envelope defines the framework for describing the information content and how to process content, encoding program objects into rules for XML objects, and executes remote procedure calls (RPCs). SOAP can run on any other transport protocol. For example, you can use SMTP, that is, the Internet email protocol to pass the SOAP message, which is very tempting. The head between the transport layers is different, but the XML payload is maintained. Web Services hopes that different systems can call each other with "Software Dialogue" to break the Software Application, Website and Various Devices, implement "web seamless integration" goals. .
3.wsdl
Web Services Description Language WSDL is an official description document that is provided in a machine-read manner and is used to describe Web Services and its functions, parameters, and return values. Because it is based on XML, WSDL is both a machine readable, and it is a man read.
4.UDDI
The purpose of UDDI is to establish standards for e-commerce; UDDI is a web-based, distributed, implemented standard specification for web service, information registry, which also contains a set of companies to provide themselves. Web Service registration to achieve the implementation of the access protocol of other companies to discover.
