Protocol for the Multicast Web Tuner

Evolution of a request

1)    The client requests file X from it's proxy.

2)    The proxy checks it's local cache for file X.  If the file is in the cache, it is returned to the client.

3)    File X was not in the proxy cache, the proxy request file X from the web server.

4)    The web server retrieves file X from it's file system.

5)    The web server multicasts file X to the cache of the requesting proxy and to any other proxies which are subscribed to the file X channel.

6)    The web server responds to the requesting proxy, instructing it to check again in the cache.

7)    The proxy checks it's local cache for file X' and finds it.

8)    The proxy returns this file to the client.

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This page written and maintained by Amy S. Hughes.
Please mail me any problems with or comments about this page.
Last modified May 13, 1997.