For security reasons, sensitive user inputs and application output must be encrypted. Most business-oriented web applications encrypt all or some of the communication flow between the browser and Application Server. Online shopping applications encrypt traffic when the user is completing a purchase or supplying private data. Portal applications such as news and media typically do not employ encryption. Secure Sockets Layer (SSL) is the most common security framework, and is supported by many browsers and application servers.
The Application Server supports SSL 2.0 and 3.0 and contains software support for various cipher suites. It also supports integration of hardware encryption cards for even higher performance. Security considerations, particularly when using the integrated software encryption, will impact hardware sizing and capacity planning.
Consider the following when assessing the encryption needs for a deployment:
What is the nature of the applications with respect to security? Do they encrypt all or only a part of the application inputs and output? What percentage of the information needs to be securely transmitted?
Are the applications going to be deployed on an application server that is directly connected to the Internet? Will a web server exist in a demilitarized zone (DMZ) separate from the application server tier and backend enterprise systems?
A DMZ-style deployment is recommended for high security. It is also useful when the application has a significant amount of static text and image content and some business logic that executes on the Application Server, behind the most secure firewall. Application Server provides secure reverse proxy plugins to enable integration with popular web servers. The Application Server can also be deployed and used as a web server in DMZ.
Is encryption required between the web servers in the DMZ and application servers in the next tier? The reverse proxy plugins supplied with Application Server support SSL encryption between the web server and application server tier. If SSL is enabled, hardware capacity planning must be take into account the encryption policy and mechanisms.
If software encryption is to be employed:
What is the expected performance overhead for every tier in the system, given the security requirements?
What are the performance and throughput characteristics of various choices?
For information on how to encrypt the communication between web servers and Application Server, please refer to Chapter 9, Configuring Security, in Sun Java System Application Server Enterprise Edition 8.1 2005Q2 Administration Guide.