Patent ID: 8250301

Claim:
A method to maintain freshness of cached content based on demand for the cached content and remaining expiration time of the cached content, the method comprising: (a) storing in a cache, by an appliance, an object served by a server in response to a first request from a client, the cached object comprising an expiry; (b) receiving from the client, by the appliance, a second request for the object; (c) determining, by the appliance in response to receiving the second request, a duration to the expiry of the cached object is less than a predetermined threshold; (d) requesting, by the appliance in response to the determination, the object from the server prior to the expiry of the cached object; (e) storing in the cache, by the appliance, an update to the object stored in the cache using the object received from the server in response to the request of the appliance.