Subject: Why are Usenet news postings out of sequence?

29. *****

 Q: Why are Usenet news postings out of sequence?

 A: The Usenet news postings travel at different speeds from the
different parts of the net, and parts of the net may occasionally be
down along the feed. Thus the news postings arrive at differing,
volatile lags.
   Take a look at the "Date:" line in the posting's header. You'll
see much variation and will note that quite a lot of the postings
are out of chronological sequence. It is not at all uncommon to see
replies to postings before seeing the original posting which is
being replied to.
   Nevertheless, the newspostings are numbered sequentially at the
receiving sites. The numbering is unique to each receiving site.
Hence you cannot identify a posting by its number (not at least to
anyone outside your own site)! Don't to refer to a posting by the
sequential number number even if your own newsreader program may
display and use these numbers. (The only way to identify a posting
unequivocally is from the "Message-Id" line from the posting's
header.)
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