Intergrated and Classic

IIS7 Application Pools has two modes, One isIntegrated, One isClassic. If you use the Integrated mode, you need to modify the configuration file for the custom httpModules and httpHandlers, and transfer them to the <modules> and

What is the difference between IIS7 and IIS6?

IIS7.0 Integrated mode:Asp.net modules and handlers from <system. webServer> <modules> and

IIS7.0 Classic mode:<Modules> and

 

Classic vs Integrated

Classic mode(The only mode in IIS6 and below) is a mode where IIS only works with ISAPI extensions and ISAPI filters directly. in fact, in this mode, Asp.net is just an ISAPI extension (aspnet_isapi.dll) and an ISAPI filter (aspnet_filter.dll ). IIS just treats Asp.net as an external plugin implemented in ISAPI and works with it like a black box (and only when it's needs to give out the request to ASP. NET ). in this mode, Asp.net is not much different from PHP or other technologies for IIS.

The classic mode is the only mode for IIS6.0 and earlier versions (only for isapi extension and isapi filters ). In this mode, asp.net is just a plug-in that implements ISAPIEXTENSION and isapi filter (aspnet_isapi.dll, aspnet_filter.dll). IIs only forwards specific requests to Asp.net, PHP and Other plug-ins hosted in IIS are the same.

 

Integrated mode, On the other hand, is a new mode in IIS7 where IIS pipeline is tightly integrated (I. e. is just the same) as Asp.net request pipeline. ASP. NET can see every request it wants to and manipulate things along the way. ASP. NET is no longer treated as an external plugin. it's completely blended and integrated in IIS. in this mode, Asp.net HttpModules basically have nearly as much power as an ISAPI filter wocould have had and Asp.net HttpHandlers can have nearly equivalent capability as an ISAPI extension cocould have. in this mode, Asp.net is basically a part of IIS.

However, in the integration mode, IIS MPs queues are closely integrated with Asp.net's request MPs queues, and Asp.net can be fully controlled to access the entire MPs queue. Asp.net is not used as an external plug-in, but fully integrated into IIS. In this mode, Asp.net HttpModules and ISAPI Filter have equivalent control. Asp.net HttpHandlers and ISAPI Extension have equivalent control. In other words, Asp.net is already part of IIS.