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Path: utzoo!utcsri!petera
From: petera@utcsri.UUCP (Smith)
Newsgroups: net.sources
Subject: UUENCODE/DECODE format (it needs checksums me thinks)
Message-ID: <2270@utcsri.UUCP>
Date: Tue, 4-Mar-86 09:28:38 EST
Article-I.D.: utcsri.2270
Posted: Tue Mar  4 09:28:38 1986
Date-Received: Tue, 4-Mar-86 09:35:06 EST
Distribution: net
Organization: CSRI, University of Toronto
Lines: 42


    How many times have we seen uuencoded stuff get screwed up somewhere
on the net. It has happened with every binary I have seen on the net so far.
I think it is time that we overhaul uuencode/decode to do two things. 

    First it should split large files into chunks small enough to allow
transmission by all the mailers on the net. Second it should provide some
checksum information to avoid the kind of things that have happend with
PC-LISP. After writing PC-LISP I don't have time to work on this but 
I think the entire net would benefit from such a program. As a side 
thought perhaps the program could run a compression algorithm first before
encoding. We would cut down the net traffic for binaries significantly
this way.

    One checksum per block would be sufficient. Then when you tried to 
assemble the blocks and one was bad you could request that someone 
resend you that block. Eg.


block: 1 of: 15 of: pc-lisp.exe
Mxxxxxxxxxxdddddddddddddxxxxxxxxxxxxxxx.....
Mxxxxxxxxxxdddddddddddddxxxxxxxxxxxxxxx.....
Mxxxxxxxxxxdddddddddddddxxxxxxxxxxxxxxx.....
M......
........
M......
Mxxxxxxxxxxdddddddddddddxxxxxxxxxxxxxxx.....
Mxxxxxxxxxxdddddd
sum:10234

   The encoding function sould split the entire binary into blocks and
place them in files called say 'pc-lisp.000,pc-lisp.001 ....'. It would
be pretty simple to call uuencode as a subroutine to do this. Computing
a checksum should be very carefully done to aviod machine dependencies.

   Of course this is just what I would like to see, perhaps we could 
thrash out the general specs and then let someone go on it.

   What do you lot think?

		Peter Ashwood-Smith
		University of Toronto.