Web Service brief concept, Learning Record !, Webservice

Web Service brief concept, Learning Record !, Webservice
The Web Service Platform requires a set of protocols to create distributed applications. Any platform has its Data Representation Method and type system. To achieve interoperability, the Web Service platform must provide a standard type system for communicating different types of systems in different platforms, programming languages, and component models. These protocols include:XML and XSDA Scalable Markup Language (a subset of a standard universal Markup Language) is the basic format for data representation on the Web Service platform. In addition to ease of creation and analysis, XML has the primary advantage of being independent from the platform and the vendor. XML was created by the World Wide Web society (W3C). XML SchemaXSD developed by W3C defines a set of standard data types and provides a language to extend this data type. The Web Service platform uses XSD as the data type system. When you construct a Web Service in a language such as VB. NET or C #, to comply with the Web Service standard, all the data types you use must be converted to the XSD type. To enable it to be transmitted across different organizations on different platforms and software, you also need something to wrap it. This is a protocol, such as SOAP. Xml web serviceSOAPSOAP is the Simple Object Access Protocol. It is a lightweight Protocol used to exchange XML (a subset of standard General Markup Language) encoding information. It has three main aspects: XML-envelope defines a framework for describing information content and how to handle content, encodes program objects into XML object rules, and executes Remote Procedure Calls (RPC). SOAP can run on any other transmission protocol. For example, you can use SMTP, or the internet email protocol, to transmit SOAP messages, which is tempting. The headers in the transport layer are different, but the XML payload remains the same. The Web Service allows different systems to call each other in the form of "software-software conversation", breaking the incompatibility between software applications, websites, and various devices, achieve the goal of "seamless Web-based integration.WSDLWeb Service Description Language (WSDL) is a language based on XML (a subset of the standard General Markup Language), which is provided by machines in the form of formal description documents, describes the Web Service and its functions, parameters, and return values. Because it is based on XML, WSDL is machine readable and human readable.UDDIThe purpose of UDDI is to establish standards for e-commerce. UDDI is a set of Web-based, distributed, and standard standards for implementing information registration centers for Web Services, it also contains a set of access protocols that enable enterprises to register their own Web services so that other enterprises can discover.Call RPC and message passingWeb services are actually implementing communication between applications. There are two methods for communication between applications: RPC Remote Procedure Call and message transmission. When RPC is used, the client calls the Remote Process on the server. Generally, a remote object is instantiated and its method and attributes are called. The RPC system tries to achieve the transparency of a location: the server exposes remote object interfaces, and the client is like the interfaces of these objects used locally, in this way, the underlying information is hidden, and the client does not need to know the machine on which the object is located.