RE: IPCOMP and IPSEC

Avram Shacham <shacham@cisco.com> Fri, 05 June 1998 05:46 UTC

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Date: Thu, 04 Jun 1998 22:45:47 -0700
To: Robert Moskowitz <rgm-sec@htt-consult.com>
From: Avram Shacham <shacham@cisco.com>
Subject: RE: IPCOMP and IPSEC
Cc: ipsec@tis.com, ippcp@external.cisco.com, Stephen Waters <Stephen.Waters@digital.com>
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At 12:01 PM 6/4/98 -0400, Robert Moskowitz wrote:

>TCPng needs to add intelligent compression (that is interact with the
>application).  There is could have history.

In previous discussions of compression at level 4, several people correctly
pointed that TCP-compression may reduce the number of IP packets while IP
compression can only reduce the size of each packet. Fewer IP packets may
enhance performance even more than utilizing compression history.

But - and this may be a BIG implementation obstacle - the current
compression algorithms require ~16KB of compression and decompression
context for _each_ connection.  In other words, 16KB per socket...

Also, UDP is still a useful L4 protocol and no stateful compression is
possible here either.

Regards,
avram