Re: IBM patents tunneling HTTP through another protocal

Jim Gettys (jg@pa.dec.com)
Fri, 5 Jun 1998 09:07:23 -0700


Examples:

1) The tunneling of the X Window System protocol through various compression 
servers, which know how to translate that protocol to a more compact
representation and back again.

This was done by a Stanford prof (name slips my mind, but I can regenerate
it) years ago (late 80's is in my mind), and a product version appeared 
as the Serial Line X work that came out of NCD and the X Consortium well 
before the application date of the IBM patent.

The patent claims of "Differencing, caching or protocol reduction techniques 
increase performance over the external communication link. " are certainly
present in this system, both differencing and caching.

2) the tunneling of the IP protocol through chaosnet protocols, done
widely at MIT in the 1983 time frame.  Here TCP's behavior in the
face of packet loss (particularly at the time) was mitigated somewhat
by Chaos Net's more agressive retransmission strategy.

3) Both SLIP and PPP do differencing and caching on the TCP/IP headers
to increase performance; these have been around for many years.

The idea, as I understand it, has been around for a long time.  Examples
1 and 3 above apply most closely, that occur to me without much thought,
and long predate the patent application.
				- Jim Gettys