Professional Microsoft IIS 8

Core Server and Modules

IIS 8.0 provides a sleek core server system cut down to the bare bones of a high-performance and robust processing engine. The basic functionality is broken into four basic components that act as the foundation of arguably the most innovative and flexible web server system ever released:

• Http.sys — The HTTP listener does nothing more than listen on port 80 for inbound web requests and then pass those requests to the IIS 8.0 core.
• WAS — The Windows Process Activation Service manages the worker process and application pool configurations. WAS allows you to run a website that uses a protocol other than HTTP — for example, using the TCP protocol for hosting a web service through a WCF listener.
• WWW Service — The World Wide Web Publishing Service is a listener adapter for the HTTP listener (i.e., Http.sys). The WWW Service is responsible for updating Http.sys, the configuration of Http.sys and alerts WAS when a request enters the request queue.
• w3wp.exe — One or more worker processes that handle all the remaining request processing.

At first glance, the IIS 8.0 core server appears similar to previous versions. IIS 6.0 introduced the concept of independent worker processes to isolate independent applications running on the same physical server and thereby prevent a failure in one application from affecting any other. Figure 11.3 depicts the IIS 8.0 structure, highlighting the basic components identified above.

Figure 11.3

There is no significant difference ...