ASP.NET 2.0 Provider Model

The ASP.NET 2.0 provider model was designed with the following goals in mind:

1. To make ASP.NET state storage both flexible and extensible
2. To insulate application-level code and code in the ASP.NET run-time from the physical storage media where state is stored, and to isolate the changes required to use alternative media types to a single well-defined layer with minimal surface area
3. To make writing custom providers as simple as possible by providing a robust and well-documented set of base classes from which developers can derive provider classes of their own

It is expected that developers who wish to pair ASP.NET 2.0 with data sources for which off-the-shelf providers are not available can, with a reasonable amount of effort, write custom providers to do the job

For more click here http://msdn2.microsoft.com/en-us/library/aa479030.aspx

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