Re: K-of-N information dispersal for Mixmaster

[David Hopwood <david.hopwood@zetnet.co.uk>]

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Nomen Nescio wrote (on alt.privacy.anon-server and sci.crypt):
> 
> Problem.  In the mixnet remailer system, large messages
> are split up into a sequence of short fixed-size chunks,
> mailed through different chains, and reassembled at the
> exit point.  If one or more of the pieces fails to arrive,
> reassembly fails and the entire message is lost.
> 
> Wouldn't this be a good case for using an Information
> Dispersal Algorithm which is redundant enough to allow full
> recovery of the original data even in a lossy environment?
> 
> This would make the remailer system fairly tolerant of high
> rates of dropout, single-packet delays, local gridlock, etc,
> with only 10%-20% overhead even for very large split messages.
> 
> Would this be an issue to raise with Lance Cottrell, or has
> he passed the mantle to another vic^H^H^H maintainer?

I suggest discussing it on the mixminion-dev mailing list, which is
designing the Type III remailer protocol (archive and subscription info
at <http://archives.seul.org/mixminion/dev/>).
See <http://www.mixminion.net/> for a draft paper on the design.

My immediate take on this is that it's an end-to-end issue, and does not
require support in intermediate nodes. But yes, it would probably be a
good idea to support an IDA when fragmenting/reassembling messages.

- -- 
David Hopwood <david.hopwood@zetnet.co.uk>

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