kelvin@atanasoff.cs.iastate.edu (Kelvin Nilsen) (07/17/89)
We are investigating the possibility of acquiring a port server that would
connect incoming modem lines and terminals in student labs with several
host computer systems. Although the host computers are all on Ethernet,
we are generally suspicious of, but will consider, port servers
that use ethernet connectivity to talk to the host computers. The
difficulty we have experienced with this configuation is that the large
amount of buffering performed by ethernet layers confuses screen movement
and updating optimizations that are typical of Unix full-screen software.
We are interested in whatever products you might have experience with.
Assuming that we eventually end up with a serial-to-serial switch, our
preliminary requirements might be summarized:
available in a basic configuration that switches 15 incoming lines
to 30 outgoing lines.
upgradable to a configuration that switches 150 incoming lines to
150 outgoing lines.
configurable so that internal buffering can be restricted to a
small size -- this requires real-time response and no flow control
on individual lines...
support for baud rates of up to 38.4 Kbaud
upgradable to a configuration that directly supports SLIP (in this
configuration, we would expect the port server to talk to hosts
via ethernet, and to remote terminals via RS-232 using SLIP protocol)
We would also be interested in whatever advice your combined net wisdom
might have for improving our "requirements specification".
Thanks
Kelvin Nilsen/Dept. of Computer Science/Iowa State University/Ames, IA 50011
(515) 294-2259 kelvin@atanasoff.cs.iastate.edu uunet!atanasoff!kelvin