[From nobody Thu Jul 24 13:54:56 2014
From: "Brian Glendenning" <bglenden@aoc.nrao.edu>
To: "Guillermo Delgado" <gdelgado@eso.org>
Subject: RE: data link
Date: Tue, 21 Sep 1999 08:46:28 -0600
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Partly in response to your question I had the ALMA-US science group
reconsider these numbers. While these numbers aren't official yet, I'd be
surprised if they change significantly.

These then are the numbers expected for the first few years of science
operation:

Maximum sustainable raw data rate	- 30MBytes/s
Average raw data rate			- 3 MBytes/s

If not even the average can be obtained than there is no option other than
shipping tapes. If the maximum can be obtained the principal result is that
the observer can get his data in something like real-time rather than having
it dribble out at 3MB/s.

If images are produced automatically in Chile, then this would approximately
double the required average data rate (this is a very gross estimate, it
depends on the mix of observing proposals for an instrument the like of
which has never been built!).

So, I'm afraid there is no clean answer to your question. There would be a
definite change in the operational model (what gets done in Chile, what
elsewhere) as the available BW goes from <3 to 3 to 6 to 33 MBytes/s.

I would think the other uses of BW would be modest - I'd guess that voice
circuits, video conferencing, and general computer access could be
accommodated on 1MByte/s, and probably less (I can try to do a calculation
if this number appears to be important).

Cheers,
Brian
]