[comp.dcom.lans] tn3270 for PCs with Excelan cards

anderer@vax1.acs.udel.EDU (David G Anderer) (02/08/89)

Here's a convoluted problem:

We've got several classrooms of IBM PCs (and ATs and PS/2s) each running
on their own Novell SFT 2.1 LAN.  The machines are connected via Thin
Ethernet and use Excelan cards (205Ts, 215Ts for MCA.)  This is a
'supported' setup from Novell and works nicely.

Some of these LANs are also connected out to our ProNet-80 campus backbone.
This backbone connects to the computing center where most of the central
mainframes are located.

We bought the Excelan cards because they would allow the PCs to maintain
simultaneous sessions to the Novell servers (XNS) and to the mainframes
(Excelan telnet, tcp/ip).  Again, this all works nicely.

However, one mainframe we need to connect to is an IBM 3090.  It seems
that machine only knows how to talk to 3270 terminals over a telnet
(WISCNET) connection.  The version of telnet Excelan ships can only
pretend to be a VT-52, -100, or -220.  Thus the problem.

I can see a couple of solutions here:

	1. Have the 3090 (running VM) understand how to handle a VT-100
	via telnet.  I'm told there is a package called SIM3270 that
	does this, but I'm also told people here are uncomfortable with
	the way it's implemented.

	2. Obtain a version of telnet that runs on the Excelan card and
	does 3270 emulation.

	3. Obtain source for a PD version of telnet that does 3270 emulation
	(but doesn't support the Excelan card) and add Excelan support.
	Excelan does sell a socket library for their card which might
	make this easier.

#1 seems unlikely from here.  I'd like to find something for #2 or #3.
Are there answers out there for these, or other solutions I haven't
thought of?

Dave Anderer
Academic Computing and Instructional Technology
University of Delaware

anderer@vax1.acs.udel.edu
-- 
Dave Anderer
Academic Computing and Instructional Technology
University of Delaware

shadow@uafhp.uucp (Shadow) (02/09/89)

In article <2796@udccvax1.acs.udel.EDU>, anderer@vax1.acs.udel.EDU (David G Anderer) writes:
> Here's a convoluted problem:
> 
> 
> However, one mainframe we need to connect to is an IBM 3090.  It seems
> that machine only knows how to talk to 3270 terminals over a telnet
> (WISCNET) connection.  The version of telnet Excelan ships can only
> pretend to be a VT-52, -100, or -220.  Thus the problem.
> 

At the University of Arkansas at Fayetteville, we have a big blue machine too.
I have to log into it for 370 assembler class.  I prefer the UNIX environment,
but an HP doesn't DO that!  We have both SIM3278 and tn3270 (UNIX) and I have
tried both.  I must admit, I prefer SIM3278!  It supports multiple big blue
sessions and has on-line help and works very well (as well as your terminal
emulation software...).  tn3270 seems kind of primitive.  It would be very
nice if it had the features of telnet, but if it does, I can't seem to find
them.  I hope this is of help to you...

Shadow

berger@clio.las.uiuc.edu (02/10/89)

In our lab at the Univ. of Il. Dept. of Statistics, we have a bunch of
3270-AT's, so we only have a handful of PC's with the problem.  We have
a special account that runs tn3270 on one of our Suns, and the networked
PC's use a Sun as a protocol translator.

Source code for tn3270 is available, but it looks like it would take a
fair amount of effort to make it run in your configuration (though a
PC-resident version has been done).