On Tue, Sep 20, 2005 at 06:19:35PM -0400, Evan Daniel wrote:
> On 9/20/05, Matthew Toseland <toad at amphibian.dyndns.org> wrote:
> > Any ideas for splitfile FEC algorithms apart from the onion code we use
> > now (vandermonde codes)?
> 
> Reed-Solomon codes?  They're (iirc) computationally efficient, have
> flexible settings for redundancy levels, don't care which blocks have
> errors, and can correct as many missing blocks as there are redundant
> blocks (or half that number of blocks with errors the decoder doesn't
> know about).  The relevant research was done in the 1960s, so I highly
> doubt there are patent issues.

http://www.4i2i.com/reed_solomon_codes.htm

How much redundancy do we need? 0.5 uses 50%, which would probably be
extremely slow with R/S. Also, it would have to be segmented, just as
Onion.

> Evan Daniel
-- 
Matthew J Toseland - toad at amphibian.dyndns.org
Freenet Project Official Codemonkey - http://freenetproject.org/
ICTHUS - Nothing is impossible. Our Boss says so.
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