Web Service is a new web application branch, they are self-contained, self-description, modular applications, can be published, locating, via web calls. Web Service can perform any feature from a simple request to complex business processing. Once the deployment, other Web Service applications can discover and call their deployment services. Web Service is an application that uses standard Internet protocols, like hypertext transport protocols (HTTPs), and XML, which reflects the programming of the Internet and intranet. Web services can be considered as component programming on the Web. 1 Historical Web is widely used: ◆ TCP / IP: Universal Network Protocol, used by various devices ◆ HTML: General User interface, you can use HTML tag display data ◆ Java: Write a universal programming language that can be run in any place ◆ XML: General Data Expression Language, easy ways to transmit institutional data on the web is its feature is the foundation of Web Services. 2 The trend of Web development is more dynamic ◆ Bandwidth bandwidth is cheaper, easy to get ◆ Memory storage is cheaper, more easy to get ◆ General calculations become more important: a large number of equipment, such as mobile phones, pages, computers, PCs, already It becomes common on the Internet, the platform becomes more diversified, and the cross-platform technology like XML is more important 3 What role does the Web Services play? These trends described above means that more intelligent processing, operation, and summary content are very important. Let's take a look at the four trends indicated by the web services: ◆ More content: A web service must be merged from multiple different sources, including stock, weather, news, etc. in the traditional environment Such as inventory level, shopping order or directory information, etc., all from the backend system ◆ Bandwidth is cheaper: Web Services can distribute various types of content (audio, video stream, etc.) ◆ Storage is cheaper: Web Services must be smart Handling a lot of data, meaning that technologies such as database, LDAP directory, buffer, and load balancing software are used to maintain scalable capabilities ◆ General Calculations more important: Web Services can't ask customers to use a version of Windows traditional browser, must Supports a variety of equipment, platforms, browser types, and various content types. 4 Two important technologies To achieve such a goal, Web Services should use two technologies: ◆ XML XML is a great way to transmit structured data on the Web, and Web Services should operate data in a reliable automatic way, HTML is not Meet the requirements, and XML can make Web services easy to process data, its contents and representation of the separation is very ideal ◆ SOAP SOAP uses XML messages to call remote methods so that Web Services can pass through the HTTP protocol POST and GET methods and remote machines Interaction, and SOAP is more robust and easy to use. Other images UDDI and WSDL technology are closely combined with XML and SOAP technology for service discovery.
