Web应用服务器研究综述

A Survey on Web Application Servers

Web应用服务器是Web计算环境下产生的新型中间件,为创建、部署、运行、集成和管理事务性Web应用提供一个跨平台的运行环境,被认为是自关系型数据库以来最令人激动的企业应用技术.诸多IT企业纷纷推出其各自的Web应用服务器产品和系统,学术界也对这种热门领域产生了浓厚的兴趣.在分析Web计算环境下传统中间件发展所遇到的问题的基础上,介绍Web应用服务器的起源和发展、运行模式以及评测基准,然后对Web应用服务器研究现状进行综述,主要包括Web应用服务器的定义、体系结构、组件容器、分布事务处理、负载平衡、高速缓存、Web Service等研究热点和关键技术.根据评测基准,对若干主流Web应用服务器从功能和性能两个方面进行分析和比较.此外,还指出了Web应用服务器目前存在的不足以及未来的发展趋势.

Web application server (WAS), which is considered to be one of the most exciting milestones of enterprise software technology since the relational database and has become very popular in the last few years. It solves the problems in applying traditional middlewares to web computing environment and provides web middleware platforms that support for the deployment, integration, and execution of transactional web applications. Attention to the new category of middleware has been drawn from the academia and software industry. The current state-of-the-art of Web application servers, including what is a web application server and its functionality, architectural model, component container, transaction processing, load balancing, mid-tier caching, web services and analysis criteria etc., are outlined. Using the Ecperf benchmark, a comparative study among some leading Web application servers is presented by evaluating their functions and performance. Lastly, some open issues about WASs are discussed, and the future direction of WASs is pointed out.