MIME boundary strings

Jacob Palme <jpalme@dsv.su.se> Thu, 22 August 2002 09:28 UTC

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Date: Thu, 22 Aug 2002 11:27:15 +0200
To: ietf-822@imc.org
From: Jacob Palme <jpalme@dsv.su.se>
Subject: MIME boundary strings
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MIME specifies that the boundary string between body parts
must be a string which does not occur in the body part
itself. This goal can be achieved in two ways:

(a) Try out different boundary string, until a string can
     be found which does not occur.

(b) Select a sufficiently long random boundary string,
     that the probability that it occurs in the body
     part is negligible. This method is not really
     permitted according to RFC 2046.

I have an impression that many mail programs
use method (b). And that some use method (b) but
do not even select a really random boundary string.

Jacob Palme <jpalme@dsv.su.se> (Stockholm University and KTH)
for more info see URL: http://www.dsv.su.se/jpalme/