[dtn-security] Including fragment offset in the correlator doesn't prevent all fragment collisions.

Amy Alford <aloomis@sarn.org> Tue, 19 March 2013 23:24 UTC

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Date: Tue, 19 Mar 2013 19:24:24 -0400
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From: Amy Alford <aloomis@sarn.org>
To: dtn-security <dtn-security@irtf.org>
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Subject: [dtn-security] Including fragment offset in the correlator doesn't prevent all fragment collisions.
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A bundle can be fragmented multiple times independently, so a node may
receive multiple fragments with the same offset and length that have
traveled different paths (and accumulated different BSP blocks along the
way).  Collisions in the correlator values once the bundle is reassembled
are inevitable.
- Amy