Well, I don't think any policy based on changing the limit from 300k to
some other value is going to work, apart from the fact that it is
something that would require yearly updates. We have countries connected
at sub-9.6k speed, that is all they can afford and they should certainly
be allowed to choose which files they want to let through and which ones
they want to trash, given that there isn't enough bandwidth to send
everything. On the other hand, there is no reason two US users should be
limited to something as ridiculous as 300k. So even though a common limit
would make life easier for servers like LISTSERV, which could then be
taught not to send larger files to remote users, I'm afraid it is simply
not a realistic goal.
In EARN there has never been any limit. Initially this irritated me very
much, as high energy physicists were happily sending million-records
files on a regular basis which statistically never made it through, as
the lines never stayed up long enough to send that much data (we're
talking about several hours). Since there was no limit, we were not
allowed to get rid of them unless there was an emergency, so what
happened is that we just had to wait until we had an emergency.
Fortunately, it didn't take very long: the more the files failed to make
it through, the more the physicists got impatient and sent additional
copies, to "push" the ones further up the queue (exact same technique as
for batch jobs). Eventually the spool reached 90%, we had an emergency,
and we were able to legally dispose of the trash - until next time. Not a
satisfactory situation, since the files kept using bandwidth until a
carrier drop occured and the transfer was aborted.
But now that we have a reasonably fast backbone, I am happy that there is
no limit, since it means bureaucratic sites won't trash my 300k files on
the basis that they might use up 1 or even 2 seconds of a poor T1 line.
The limit really has to be based on the speed of the lines and the size
of the spool at the hub nodes, or it won't satisfy everyone. You could
perhaps agree on a limit for the "high speed" part of the network, but
you would have to allow the people operating the hub nodes that connect
"low-speed" areas (typically countries) to make their own selection based
on local policy. What you could probably specify is how the sender and
recipient should be notified if a file is purged.
Eric
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