providing tn3270 service

[Arnold D. Robbins {EUCC}]

This is a little wierd, but please bear with me.  I work in the Computing
Center at Emory University.  Along with Unix and VMS, we have a large IBM
system running VM/XA with FAL (IBM's TCP/IP product) and MVS.

Our MVS development group is getting ready to move off campus.  They will
be bridged to our main ethernet using T1/ethernet bridges.  Some of them
will have Macs running Brown TN3270, bridged to the ethernet with a
Kinetics fastpath.  The rest will either have regular ascii terminals or
PCs running a communications program.  It is these latter who need to
be able to get to our IBM system, and use the full screen interface
they're used to (we have been using 7171s up until now).

What we are planning to do is this.  Put a terminal server (like an
Annex) on the off-campus ethernet.  On campus, dedicate a small Unix
box, e.g. a Sun 3/60 or 3/80, to running tn3270.  The users with terminals
and PCs would have serial lines on the terminal server, telnet to the
dedicated Unix machine, and login to a captive account that prompts
for a terminal type and then execs tn3270 to the mainframe.

My questions are as follows:

	1) Is there anything glaringly stupid about doing this?
(Responses about the use of IBM systems to /dev/null - I'm a Unix bigot,
but I work here and have to help make this happen.)

	2) About how many simultaneous tn3270 sessions can we expect to have
running before the users notice a performance degradation? 10, 20, 40, 50?

	3) Does anyone have any better ideas?

My own intuition is that a 3/80 (the 68030 box) with 8 Meg of memory and
local disk should have no problem handling at least 25 such users and
probably 40.  But I would like to hear from anyone else who knows
differently.  Please mail your responses. I will post a summary if there's
enough interest.

Much thanks,
-- 
Arnold Robbins -- Emory University Computing Center | Unix is a Registered
DOMAIN: arnold at unix.cc.emory.edu		    | Bell of AT&T Trademark
UUCP: gatech!emoryu1!arnold  PHONE: +1 404 727-7636 | Laboratories.
BITNET: arnold at emoryu1	     FAX:   +1 404 727-2599 |         -- Donn Seeley