WebSphere Application Server for z/OS includes plug-ins to allow connections via the HTTP(S) Transport between a Web container and your configured web server.
In WebSphere Application Server for z/OS, it is faster to directly use the HTTP transport than to configure Web server plug-ins. For information about the HTTP transport, see Configuring transports. You may want to use the web server plug-ins only if you are looking for easier configuration of new application servers or applications within a cluster.
If you specify a Web server when installing the WebSphere Application Server product, the installation program changes the Web server configuration file automatically to establish a plug-in.