HTTP.sys as the protocol listener that listens for HTTP and HTTPS requests.
HTTP.sys was introduced in IIS 6.0 as an HTTP-specific protocol listener for HTTP requests.
HTTP.sys remains the HTTP listener in IIS 7 and above, but includes support for Secure Sockets Layer(SSL).
Process, Services, File, Directory并不是最重要的。最重要的是Function.
故Protocol Listeners------------>HTTP.sys 和 WCF
To support services and applications that use protocols other than HTTP and HTTPS, you can use technologies such as Windows Communication Foundation(WCF).
WCF has listener adapters that provide the functionality of both a protocol listener and a listener adapter.