經典技術文章翻譯(3):IIS7協議偵聽器（IntroducingIIS7>IISProtocolListeners）

A protocol listener is a software routine that listens on a predefined communication channel (and port), and passes transmitted data (called messages) to and from the participating server service and communicating client. IIS 7 includes five default protocol listeners: Http.sys, Net.tcp, Net.pipe, Net.p2p and Net.msmq; and additional custom listeners can be created and used. IIS 6 had only one — Http.sys. The other new protocol listeners support Microsoft`s new Windows Communication Foundation web services. With the exception of Http.sys, the other listeners require .NET Framework installation and the Windows Process Activation Service (WAS), which runs in the same Svchost process as the WWW service. However, protocol listeners can be implemented using WAS and not require IIS.

    Each listener runs in kernel mode, directly interacting with the operating system. Microsoft has thoroughly tested each protocol listener for security vulnerabilities, trying their best to ensure they are not susceptible to buffer overflows and other common security mistakes. Although finding every security vulnerability is almost impossible, Microsoft successfully defended IIS 6`s Http.sys against every attacker for over 4 years, so they have a leading example to follow. Protocol listeners can be activated in an XML configuration file called ApplicationHost.config. To minimize possible attack vectors, only the protocol listeners needed should be activated. The follow sections summarize each protocol listener.