One of the core priorities we focused on when building IIS 7 was to enable a rich .NET extensibility model that provides developers with the hooks to easily plug-in and extend the web server.
These extensibility hooks are provided in the web-server pipeline (enabling scenarios like the new IIS7 Bit Rate Throttler), within the configuration system (enabling developers to create new web.config schema settings), within the health monitoring system (enabling developers to add custom trace events), and within the admin tool (enabling developers to plug-in new admin UI modules).
We added these extensibility hooks so that anyone can easily extend and enhance the web server using .NET. We also selfishly wanted them so that we can ship regular feature packs that add additional features to the core web ...
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