Many people confuse when it comes a Web server and an application server. A Web server and an application server are different from each other although, they have some similarities. This article mentions some important differences between web server and the application server.
Web Servers
- Web servers can only provide static page services to clients. (the page displayed is the same for all users)
- Web servers are capable of serving only Web based applications.
- Web servers handle only Hyper Text Transfer Protocol (HTTP). It means clients send the request to a server with HTTP and server sends the service to client in HTTP only.
- It is not possible to add any additional functionality later to the web server.
- A Web server can be either a hardware device or a software application.
- Web servers do not make use of databases.
- Workload is not heavier in Web servers when compared to application servers.
- In many cases, Web servers are used to create the front end for application servers. This is because, it displays different web pages which might be helpful for interacting with the business logic or the databases.
- The user sends the request to the server through web browser. The Web browser converts the request to the special machine readable format and send it to the server. The server sends back the web page requested to the browser in the same machine readable format. Web browser then converts it to the use understandable format and displays the requested page.
- Some examples of Web servers are Apache Tomcat, Microsoft IIS etc.
Application Servers
- Unlike web servers, application servers are not just restricted to HTTP protocol, but can handle other protocols as well.
- Application server provide dynamic content to the users. It means different pages to different users (example: user profiles) and different pages at different times.
- Application servers are a software applications, which needs to be installed in a computer device to make it an application server. The application server is not available as hardware device.
- Application server can serve clients with both web based applications and business based applications.
- It is possible to add an extra functionality to the application server in the future.
- An application server can have the web server functionality in it. In simple terms, application server is a superset of web server.
- Workload in application servers is heavier than in web servers.
- Application servers act as mediators between the front end (user) and the back end (databases). Application servers access business logic and the databases. They can use business logic and the databases to process request they receive from the user.
- Some examples of application servers are Java application servers like JBOSS, JRUN, etc.
Both Web servers and application servers are useful for small businesses, as they host web pages and store huge number of files at a centralized location securely.