uucp to hundreds of sites

[John Carter ATLN SADM]

Posting this because mail bounced.

But the prime concern should NOT be how many at once, but how much
data to be moved, and how quickly.  If the sites are remote, the line
speed is the biggest factor - a 90K file would take ~5 minutes at 9600,
and ~17 minutes at 1200.  (Time determined from historic data on
several local systems, some on LAN at 9600, some on dialup at 1200,
transfers done at various times in the systems load cycle.)
At 5 minutes/site, you get 12 sites/hour with one 9600 baud line. 
If you have four simultaneous 9600 baud transfers, you get 48
sites/hour.  This would get the first hundred sites done in two
hours.  The question then becomes "How soon is 'immediate'
or 'simultaneous' updating?"  (Even two simultaneous uucp jobs won't
complete at the same time.)  The tradeoffs are the number of lines a
given box can support, the number of sites to update, the speed of
the lines used, how closely the 'simultaneous' updates must
coincide, the amount of $$$ available initially and for growth.
One machine running 8 concurrent uucp jobs at 9600 baud would be
capable of doing ~100 sites/hour.  If one hour is close enough for
the updates of the sites, then the need is for one machine capable
of continuous simultaneous I/O at 9600 on 8 ports, and the
installation of 9600 baud modems at all sites.  If the machine is
running just the operating system (including accounting, etc) and
the uucp transfers, then it's possible to get a lot of thru-put from
a small machine, but it's very architecture dependent.

Example:	DEC's PDP 11/70 running Unix could handle more I/O
		with a mature version of an application than an AT&T
		3B5 could running the initial port of the application,
		even though the 3B5 would usually be considered the
		more powerful of the two machines.

How much was the maturity level of the software and how much was
hardware dependent?  I really don't know, except that the 3B5
application was rated as 50% greater capacity than the 11/70
version.  

How successful would a developer be in getting a group of suppliers
to provide one each of their machines for testing?  Maybe if you
could get one each of several different Unix boxes for a period of
weeks you could do real analysis on the capabilities of the various
small Unix machines.
-- 
USnail: John Carter, AT&T, Atlanta RWC, 3001 Cobb Parkway, Atlanta GA 30339
Video:	...ihnp4!cuea2!ltuxa!ll1!nesac2!jec    Voice: 404+951-4642
(The above views are my very own. How dare you question them? :-)