Need help with error correction.

[Steve Rooke]

I have two sites, one sending a file, the other receiving.  There is a lot
of corruption at the receiving end caused by line noise.  I am not able to
use any standard form of error correction on the line but I can request
retransmission of the file, as many times as needed, over another link.

I need to be able to compair these files and reconstruct the original with
reasonable confidence.  By that I mean that if two, or more, files have the
same text at a certain point then I am reasonably confident that the text
is OK.

I orignally thought of basing this on diff by trying to understand it's
output and collecting up the lines that are not different in each file but
the error rate may be high enough to cause some corruption on each line.
I expect the routine would have to look for substrings and be able to
re-sync when characters are lost/gained.

Has anyone tried to do this sort of thing before and how did you do it,
please?  Solutions based upon diff would do, I guess, for a majority of
the time.

Thanks a lot,
Steve
-- 
Steve Rooke  steve at gapos.bt.co.uk  (...mcsun!ukc!gapos!steve)  UK + 394 693595
BT, CSD/AS, Area 106, Anzani House,   | "You roll the dice with your heart
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