Corba is based on the distributed - component technology , which provide a mechanism of " software bus " . in theory , any applicable system can be integrated into the cobra system , if they wrap up the whole package according to the regulation of cobra . therefore , cobra put forward the idea of 3 - levels structure : client , broker , server Corba是基于分布式对象技术的，它提出了一种“软件总线”的机制，理论上任何应用系统只要按corba的接口规范完成系统的包装，就能集成到corba系统中，由此corba提出了客户层、代理层、服务层的“三层”结构思想。
According to the actual condition of guizhou telecom and characteristic of technology , the oa system of guizhou telecom has adopted object - oriented technology , component technology , and j2ee technology , in the j2ee four - tier based structure , browser provides visual graphic interface , web server respond to the request of the clients , application server processes application , computation and data operation , db server stores and administrates information 在四层结构体系中，客户层( browser )为客户提供可视化图形界面； web层( webserver )相应客户请求，为客户提供所请求的数据；应用层运行应用逻辑，完成客户请求中相应的计算和数据操作；数据层( dbserver )储存、管理数据信息。
In order to change the disadvantages of two - tier structure mode , the three - tier structure mode was given . three - tier c / s structure mode already resolve most of the problems of two tier c / s structure , and can be used by large users , high stability , but the client tier and application tier must be setup usually . in three - tier b / s structure mode , the client tier is browser , it must not be setup 为改善两层结构的不足，而提出了三层结构， c s三层结构虽然解决了两层结构中无法满足大量用户同时访问的问题，稳定性也高，但由于客户层和应用层一般都需要安装，尤其是客户层的软件每台计算机都要安装配置，系统的灵活性差，维护也不方便。
The middle tier are web server and web application , the web server is only setup once , the application must not be setup usually , and it has good expansibility and convenient recomposition and short development cycle , so three - tier b / s structure become the ma in structure in the domain gradually . but in parent , the method on three - tier b / s structure has many defects . now people need a kind of method , which is convenient , powerful , more security , high stability , good expansibility 而b s三层结构由于其客户层是浏览器，不需要安装，应用层一般也不需要安装，使得系统比较灵活、易于维护，开发周期也比较短，所以b s三层结构，逐渐成为业界的主流，但目前基于b s三层结构的系统开发方法都存在着各种各样的缺陷，目前急需一种开发简便，开发周期短，功能强大，安全性高，运行稳定，可扩展性好的开发方法。
By integrating related theories and methods of system engineering ^ software engineering and computer science , this paper has discussed the b / s model based on java technique and systematically analyzed how to realize b / s model ' s 3 tiers by applying java technique 本文综合运用了系统工程、软件工程、计算机科学等多门学科的理论和方法，对基于java技术的b s模式进行了探讨，全面、系统分析了java技术如何在b s架构的三个层次(即客户层、应用层、数据层)实现的技术。
Secondly , according to the long - term research on the data mining commercial application of telecommunication increment profession , this article elaborate three - level systems structure of the data mining commercial application platform , namely the customer level , the intermediate level and the data service level , and make detailed description to each level ’ s main function 其次,在多年的电信增值行业数据挖掘商业应用研究的基础上,本文论述了数据挖掘商业应用平台的三层(即客户层,中间层和数据服务层)体系结构,并对各层的主要功能进行了详细的阐述。
Then , considering web site ' s characteristics , user and web data ' s diversity and distributed computation characteristics of network , the paper builds a recommendation system model based on web data mining and relates every function module in detail . furthermore the paper integrates all modules in recommendation system model into b / s three layers based on corba criteria : customer layer , server layer , database layer 接着，考虑在internet上web站点的各种特点、用户和数据多样性的特点以及网络处理的分布性，构建了一个基于web数据挖掘的商务网站推荐系统模型，并对系统中各模块的功能给予了详尽的说明，同时用corba规范集成各基于web数据挖掘两务网站推荐系统的研究摘要个模块为一个b s三层结构的推荐系统，将其分成客户层、服务器层和数据层。
