[2315] in cryptography@c2.net mail archive
Chaffing and winnowing - efficiency improvements
daemon@ATHENA.MIT.EDU (Colin Plumb)
Mon Mar 23 13:54:37 1998
Date: Mon, 23 Mar 1998 11:13:26 -0700 (MST)
From: Colin Plumb <colin@nyx.net>
To: cryptography@c2.net
I can make a couple of observations. One is that since the MAC
attached to chaff packets is arbitrary, you might as well use the
wheat's MAC. E.g. you'd send (0,0,4529), (0,1,4529), (1,0,2752),
(1,1,2752), (2,0,9136), (2,1,9136), etc.
This, however, lends itself to the obvious compression technique of
omitting the actual data bits and sending just (0,4529), (1,2752),
(2,9136), etc. Rivest's Charles, along with a friend (Dawn) at Bob's
end, could easily convert Alice And Bob's legitimate communications to
this form, and Dawn could generate the redundant packets to try at the
far end.
This is getting *closer* to practical. Of course, anything is
practical if nothing better is available due to GAK.
--
-Colin
