Scalable Universal Data Exchange

With the development of the global economy, electronic data exchange has become more and more important for the enterprise to take part in the trade competion. Traditional EDI isn't fit for the requirements of the contemporary commerce, so it will be taken the place by the new XML based Internet EDI. In this paper, we want to provide a secure, reliable and extensible generalutility data exchange framework (EGDEF) for enterprise applications. By introducing the concept of the Web Service, We provide a synthetical solution based on the information framework of the Web Service.With the coming forth of the Web Service, a series of protocols and specifications emerge, such as the early WDDX, XML-RPC, WIDL and the current SOAP, WSDL, UDDI. The Web Service is a new and hotspot techonology in XML field, but there is little research about it inland now.In this paper we will first probe into the concept of the Web Service and its information framework, then we will make some analyses and comparisons about the relative protocols and specifications of the three layers of Web Service which are Web Service message protocol, Web Service description language and Web Service deiscovery mechanism. Simple Object Access Protocol (SOAP) , Web Service Description Language (WSDL) , Universal Description, Discovery and Integration (UDDI) are the three most representative and hopeful technologies, on which we will focus our minds.Upon the analyses and comparisons of the several different message protocols, we choose SOAP as the basis of the EGDET because of its simplicity, flexibility, extensibility and generalutility. But SOAP is a very simple protocol and doesn't support message transport in asynchronous, reliable, secure way and with attachments. In order to satisfy the actual requirements of the enterprises, we utilize the SOAP extensibility mechanism to make some necessary extentions and present an extensible, generalutility data exchange framework to support B2B integration applications. The extensions are as follows: asynchoronous transport mechanism upon concrete transport bindings; reliability mechanism that supports automatic retry of the meaasge document and error reporting; utilizing MIME as meassge enveloping mechanism that supports binary data and attachments tranport; utilizing S/MIME security mechanismto support secure transport. At the latter part of the paper, we give out the implementation model of EGDEF and the actual implementation of the key modules.