Web service平臺需要一套協(xié)議來實(shí)現(xiàn)分布式應(yīng)用程序的創(chuàng)建。任何平臺都有它的數(shù)據(jù)表示方法和類型系統(tǒng)。要實(shí)現(xiàn)互操作性，Web service平臺必須提供一套標(biāo)準(zhǔn)的類型系統(tǒng)，用于溝通不同平臺、編程語言和組件模型中的不同類型系統(tǒng)。在傳統(tǒng)的分布式系統(tǒng)中，基于界面(interface)的平臺提供了一些方法來描述界面、方法和參數(shù)(譯注：如COM和COBAR中的IDL語言)。同樣的，Web service平臺也必須提供一種標(biāo)準(zhǔn)來描述Web service，讓客戶可以得到足夠的信息來調(diào)用這個(gè)Web service。最后，我們還必須有一種方法來對這個(gè)Web service進(jìn)行遠(yuǎn)程調(diào)用。這種方法實(shí)際是一種遠(yuǎn)程過程調(diào)用協(xié)議(RPC)。為了達(dá)到互操作性，這種RPC協(xié)議還必須與平臺和編程語言無關(guān)。
1．Web對象
從外部的使用者的角度而言，Web服務(wù)是一種部署在Web上的對象/組件，它具備以下特征：的封裝性，Web服務(wù)既然是一種部署在Web上的對象，自然具備對象的良好封裝性，對于使用者而言，他能且僅能看到該對象提供的功能列表。
松散耦合，這一特征也是源于對象/組件技術(shù)，當(dāng)一個(gè)Web服務(wù)的實(shí)


Web service needs a platform to achieve an agreement the creation of distributed applications. Any platform that has its data methods and types of systems. To achieve interoperability, Web service must provide a standard platform for the type of system for communication between different platforms, programming languages, and components in the model of the different types of systems. In a traditional distributed system, based on the interface (interface) to provide a platform for a number of methods to describe the interfaces, methods and parameters (universe: COBAR such as COM and the IDL language). Similarly, the Web service platform must also provide a standard to describe the Web service so that customers can get enough information to call this Web service. Finally, we must also have a way to this remote Web service call. This method is a practical agreement Remote Procedure Call (RPC). In order to achieve interoperability, this agreement must also RPC platform and programming language unrelated.