[comp.protocols.tcp-ip] terminal servers w/modems

ssb@quest.UUCP (Scott S. Bertilson) (09/13/90)

  I've just been trying out the Xyplex terminal servers and was
pleased to discover that they allow a mode where a given port
can be used either for dialing in or dialing out - depending
on whether the modem sees carrier first or a host requests
a connection to the port first.  It generally works just
like I'd hope it would except that their box currently doesn't
allow hardware flow control AND modem control simultaneously.
  I've also looked at an Altos version of a 10 port CMC terminal
server which does have enough hardware lines to support both,
but doesn't support what Xyplex calls "port access dynamic".
I'm wondering if this is the case for the real CMC box or if
it's a restriction that Altos applied.
  Are there any other terminal servers other than Xyplex that
support bidirectional modem use?

  A related topic is that in order for this to be truly useful,
"uucico" and "cu" need to be able to make a TCP/IP connection.
I know that 4.3 allows this, but I'm running SCO UNIX 3.2 and
Altos version of AT&T SVR3.1.  I'm less familiar with SCO, so
I might be missing something, but as far as I know, it doesn't
allow this.  It is possible in both of these environments to
make ISO streams connections using the NLS (I'm very short on
knowledge of terms/semantics here), but as far as I can see
there is no way to make a TCP/IP connection.  Any ideas?
  The only idea I've had is that perhaps one could write a server
under streams that would accept connections and pass the data
across to a (Lachmann) TCP/IP socket.  If anyone has done this
or tried, I'd sure like to see code or fragments thereof.
			Thanks!
-- 

Scott S. Bertilson   ...ssb@quest.UUCP
			scott@poincare.geom.umn.edu

prc@erbe.se (Robert Claeson) (09/14/90)

In a recent article ssb@quest.UUCP (Scott S. Bertilson) writes:

>  I've just been trying out the Xyplex terminal servers and was
>pleased to discover that they allow a mode where a given port
>can be used either for dialing in or dialing out - depending
.....

>  Are there any other terminal servers other than Xyplex that
>support bidirectional modem use?

Yes, the Annex series of terminal servers from Xylogics and
Encore Computer has supported bidirectional ports since many
years ago.

>  A related topic is that in order for this to be truly useful,
>"uucico" and "cu" need to be able to make a TCP/IP connection.
>I know that 4.3 allows this, but I'm running SCO UNIX 3.2 and
>Altos version of AT&T SVR3.1.

If you have Streams and/or TLI access to TCP/IP, it is possible.
It's just a matter of setting up the Devices and related files
correctly (provided your system actually use HDB uucp that
the System V Release 3.1 code is delivered with from AT&T).
See the documentation for "BNU" (Basic Networking Utilities).

I recently tried this but can't remeber the details. But it
was easy. Make sure to use the "e" protocol for best performance.

-- 
Robert Claeson                  |Reasonable mailers: rclaeson@erbe.se
ERBE DATA AB                    |      Dumb mailers: rclaeson%erbe.se@sunet.se
                                |  Perverse mailers: rclaeson%erbe.se@encore.com
These opinions reflect my personal views and not those of my employer (ask him).