Large Web-based ecommerce systems are commonly structured in 3-tier architecture -
Presentation Layer, Application Layer and Persistent Layer. Many software have been developed to manage the commonality of applications
at each layer to simplify and standardize the Web application development. Web Browsers, such as Microsoft Internet Explorer, handle
presentation layer of a Web-based application. Relational Database Management Systems (DBMS) or database servers, such as Oracle, are
usually used for managing data persistent layers. An Application Server is a server program that manages, runs and serves business
applications. Top Application Servers are designed to support Java applications based Sun Microsystems' J2EE standards.
Application Server is not a operation system. We can run browsers, application servers and database servers on the same operating system.
For instance, we can run an Internet Explorer, a WebLogic server (a application server), and Oracle Database on one NT server.
Application Server is not an application. Application Server can manage and run many business applications and doesn't implement
Common Services provided by Application Servers
Java Application Servers commonly support six primary services - concurrency, transaction management, persistence, object distribution,
naming, and security.
Evaluation of J2EE Application Servers
Choosing the Right Application Servers is a complex decision making process. You choose what's best for your project considering
performance, cost and licensing/compliance, scalability and availability, efficient development, platform and sdk support/technical
Top Vendors in Java Application Servers
IBM and BEA are the two contenders in Java Application Server market. According to new research by Gartner Dataquest,
IBM has become the top vendor in the fiercely competitive market for Java application-server software. The market share for IBM's
WebSphere grew to 37% in 2002 from 31% in 2001. While market share for BEA's WebLogic slipped from 34% in 2001 to 29% in 2002.
JRun is another low cost Java Application Server that many developers like.
Development Processes and Technical Environments - Development, Test and Production
Software Configuration Management - Version Control, Build, Release Management and Process Control