"Internet Cache Protocol (ICP), version 2"

I don't think this is a 'work item' of HTTP-WG, but you might want to
be aware of a non-HTTP protocol being used by HTTP caches.
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       Title     : Internet Cache Protocol (ICP), version 2                
       Author(s) : D. Wessels, K. Claffy
       Filename  : draft-claffy-icp-v2-00.txt
       Pages     : 7
       Date      : 11/05/1996

This draft document describes the Internet Cache Protocol (ICP) currently 
implemented in a few World-Wide Web proxy cache packages.   ICP was 
initially developed by Peter Danzig, et. al. at the Univerisity of Southern
California.  It evolved as an important part of hierarchical caching on the
Harvest research project.                                                  

http://ds.internic.net/internet-drafts/draft-claffy-icp-v2-00.txt
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