Research On Enterprise Application Integration Based On Web Services

Traditional Enterprise Application Integration (EAI) technology can not adapt to the rapidincrease in the Enterprise Information Systems (EIS), and the appearance and developement ofWeb Services offers new technology for Enterprise Application Integration technology. UsingWeb Services technology to realize EAI will help to resolve all sorts of shortage in EAItechnology among distributed different-structure systems, moreover it makes the integration ofapplication programs faster, easier and more effective than before.Web Services is an open technological framework that is built up on the basis of XML and isput forward to resolve application-layer integration problem in platform-layer. Web Services useSOAP messages based on XML form to carry on data interchange, uses WSDL files to describethe interfaces, issues and finds out services through UDDI registration center, thus realizes theloose integration of business function. These characteristics are very ideal for connectingbusiness function through Web Services among and in enterprises.On the basis of analyzing those existing EAI solution, this thesis studies the EAI based onWeb Services using new Web developing technology, proposes an EAI framework based on WebServices, and designs an EAI scheme based on Web Services.The major research works and initiative points in this thesis are as follows:1. Analyzing the present situation of EAI based on traditional distributed technology,according to characteristics and types of EAI, anatomizing the advantage of EAI solution basedon Web Services compared with traditional EAI scheme.2. Analyzing Web Services protocol stack, Service Oriented Architecture (SOA) and the keytechnology (XML, SOAP, WSDL, UDDI) to realize Web Services;Analyzing and comparingJ2EE and .NET those are two major platforms to develop enterprise-layer-application WebServices, then discussing theory technology of establishing and disposing Web Services by C#language on .NET platform especially.3. On the basis of theory analysis, putting forward a framework that Web Services areapplied to module communication, application integration inside enterprise and applicationintegration among enterprises.4. Adopting the design philosophy of dividing layer, constructing EAI model, and designingan EAI scheme based on Web Services. This scheme can utilize existing software investment andkeeps the operation of the original software system as much as possible, and constructs a unifiedapplication service layer on the basis of original system, which provides external service in theway of Web Services.5. For the key problem to combining enterprises' bequeathed applications in the EAI schemedescribed above, analyzing how to understand bequeathed applications, putting forward the wayto understand bequeathed applications, and discussing the method to encapsulate them into WebServices and the encapsulation restrain which needs to be observed. For explaining the concreteoperations and steps to encapsulate bequeathed applications, developing two typical WebServices examples based on .NET platform actually:one is using SOAP Toolkit to encapsulateCOM module into Web Service, the other is using Visual Studio.NET to establish Web Servicefor visiting database.6. Analyzing the security problem existing in Web Services, and discussing safe problemsand safe technology of Web Services on transmitting layer and SOAP layer especially. Thenresearching on the principle and realization of new recommendatory security criterions, andanalyzing the security factors met by those criterions. Then, studying the security demands forEAI under the EAI framework based on Web Services, and carrying on the research that how torealize validation, authorization, confidentiality, integrality and other safe factors, providingconcrete designing methods and realizing steps to expand programming for SOAP security, toencrypt contents for guaranteeing news confidentiality, to establish XML signature forguaranteeing news integrality.Finally, mading some summaries, appraisement and prospect to the research work herein.The EAI scheme this thesis puts forward has loose coupling, simple, exoteric characteristicetc., and solves problems such as bad expansibility, high complexity, bad compatibility, whichexist in traditional EAI. With the constant development of Web Services technology, WebServices' application in EAI will bring revolutionary change for enterprises information systemsand exert a far-reaching influence on enterprises development. As a result of the importance ofenterprises information and the great researching foreground of Web Services technology, there isdefinite signification of theory and realism in the work of this thesis.