A new demo has been added in the Microsoft ISA Server demo portion.The detail of this demo is

Title: How to Configure Whether to Return Expired Objects from the Cache in ISA Server 2000

Objective: The objective of this demo is to teach you how to configure weather to return expired objects from the cache in ISA Server 2000. Objects stored in the cache are marked with a TTL. When an object's TTL passes, the object has expired. When a client requests an object, ISA Server checks to see if a valid version of the object is in its cache. If so, the object is returned. Otherwise, depending on the cache policy, ISA Server requests the object from the specified Web server. If the Web server is accessible, ISA Server retrieves the object and returns it to the client. If the Web server is not accessible, then you can configure ISA Server to return an expired version of the object from the ISA Server cache.

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