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Rob Warnock rpw3 at rigden.wpd.sgi.com
Sat Mar 9 13:22:51 AEST 1991


In article <1991Mar9.014207.16178 at odin.corp.sgi.com> jeffg at sgi.com
(Jeff C. Glover) writes:
+---------------
| Wouldn't the "compress" magic number (first longword of the file) give
| a crypt-breaker a fairly good headstart on the rest of the contents?
+---------------

Yes, indeed. But it's a constant, so remove it after compressing (with "dd"?)
and put it back at the other end after transmission and before decompressing.

The fact that what follows the header is a permutation of the "strings" for
the single characters you most often use might possibly give some aid to a
perpetrator, but much less help than the fixed header.

But in any case, don't use "crypt".


-Rob

-----
Rob Warnock, MS-1L/515		rpw3 at sgi.com		rpw3 at pei.com
Silicon Graphics, Inc.		(415)335-1673		Protocol Engines, Inc.
2011 N. Shoreline Blvd.
Mountain View, CA  94039-7311



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