WebSphere Application Server V7.0: Concepts ... - IBM Redbooks

3.1.10 Proxy servers
A proxy server is a specific type of application server that routes requests to
content servers that perform the work. The proxy server is the initial point of
entry, after the protocol firewall, for requests entering the environment.
WebSphere Application Server allows you to create two types of proxy servers:
► WebSphere Application Server Proxy
► DMZ Secure Proxy Server
WebSphere Application Server Proxy
WebSphere Application Server Proxy supports two protocols:
► HTTP
► SIP
You can configure your WebSphere Application Server Proxy to use one of these
protocols or both of them. This proxy server is used to classify, prioritize, and
route HTTP and SIP requests to servers in the enterprise, as well as cache
content from servers.
HTTP proxy
The proxy server acts as a surrogate for content servers within the enterprise. As
a surrogate, you can configure the proxy server with rules to route to and load
balance the clusters of content servers. The proxy server is also capable of
securing the transport, using Secure Sockets Layer (SSL), as well as the content
using various authentication and authorization methods. Another important
feature is its capability to protect the identity of the content servers from the Web
clients by using response transformations (URL rewriting). The proxy server can
also improve performance by caching content locally and by protecting the
content servers from surges in traffic.
You can modify an existing proxy server to perform advanced routing options,
such as routing requests to a non-WebSphere application server. You may also
modify a proxy server to perform caching.
Note: When using WebSphere Application Server for z/OS V7.0, the proxy
server uses the Workload Management component to perform dynamic
routing.
Chapter 3. WebSphere Application Server concepts 67