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From: alo@kampi.hut.fi (Antti Louko)
Newsgroups: comp.protocols.tcp-ip
Subject: TCP window size restriction
Message-ID: <1991Jan2.162810.6356@santra.uucp>
Date: 2 Jan 91 16:28:10 GMT
Sender: news@santra.uucp (Cnews - USENET news system)
Organization: Helsinki University of Technology
Lines: 20

This is a crazy idea I have been thinking of.

As we all know, the window field in the TCP protocol is 16-bit and can
thus represent only values 0 .. 65535. This limits the available
bandwidth of a single TCP connection to 65535/T octets/second. With 1
second round-trip-delay we can get at most 64 Kbytes/second.

The solution I have in mind is as follows:

TCPs at each end agree a new meaning for window sizes 65520 .. 65535.
65520 means window size 2^(65520-65504) = 2^16
65521 means window size 2^(65521-65504) = 2^17
etc.
65535 means window size 2^(65521-65504) = 2^31.

Please remember that this has to be agreed by both TCPs.

Please comment!

	Antti Louko (alo@hut.fi)