Path: utzoo!utgpu!watmath!att!rutgers!ucsd!usc!samsung!uunet!bfmny0!tneff
From: tneff@bfmny0.UU.NET (Tom Neff)
Newsgroups: news.software.b
Subject: Re: Anyone interested in end-to-end checksums in news?
Message-ID: <14922@bfmny0.UU.NET>
Date: 16 Nov 89 15:56:22 GMT
References: <14594@well.UUCP>
Reply-To: tneff@bfmny0.UU.NET (Tom Neff)
Lines: 28
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One problem with checksumming news is that if done wrong, it could
presume too much about the internal representation of articles.  If I
have an EBCDIC machine that stores all text files as fixed-length
blank-padded 80 character logical records with no concept of '\n', I
should still be able to run News.  Such machines could ignore the
Checksum field, of course.  But they're as prey to noise and article
corruption as anyone else, and deserve the benefits of the feature.

Checksumming could work if the following rules apply:

 * Start with the first nonblank line of the article body; do not
   include headers.  (Think about the "Path" field.)

 * Only checksum nonblank lines.

 * Only count characters in the graphics-64 set; use their ASCII
   numeric representations.  (Non-ASCII machines can just translate
   while computing.)

A new field like Checksum is only worth adding if practically everyone
can get some use out of it.  The above suggestions would allow lots
of different machines both to generate and check the field.

-- 
When I was [in Canada] I found their jokes like their   | Tom Neff
roads -- not very long and not very good, leading to a  | tneff@bfmny0.UU.NET
little tin point of a spire which has been remorselessly
obvious for miles without seeming to get any nearer. -- Samuel Butler.