lars@ACC.ARPA (12/27/85)
Hello Devon,
If I understand your problem correctly through several layers
of off-center description, what you want to do is to get from
a terminal attached to an X.29 pad on TRANSPAC to MIT-MC with
an 8-bit path. (Probably what you want to do involves either
graphics or Personal Computer file transfer - why else would
you need an 8-bit path).
At present, your normal path is to connect via Transpac-telenet
to an X29-pad box connected to a MICOM port-selector box at
CMU, where you log in on a CMU system of some kind, and then
do TELNET to MIT-MC. You have two problems with this:
1. Occasionally, the CMU system is down
2. You cannot get an 8-bit datapath
Did I get it right so far ?
I think your present connection is a technically poor solution,
for the following reasons:
1. Why are you going to MC in the first place ? I have heard that
the maintenance contract on the MC PDP-10 is running out on
Dec 31, and next time a major hardware problem occurs, the
machine will die. Hardly the place you want to depend on.
2. When you have a transatlantic hop in your link, you have very
long round trip delays, and it becomes important to be able to
switch between local echoing and echoplex dynamically (at least
on the long hop). Since your long hop is X.29, and your X.29
connection is two gateways from the host that switches modes,
it is highly unlikely that mode changes will propagate all the
way back to X.29. (The PAD at CMU is your X.29-to-simple-tty
gateway, the CMU host is your simple-tty-to-TELNET gateway).
You therefore want to cross into telnet as close to you as
possible, and then go TELNET on the longhaul.
I don't know much about French collaboration in the INTERNET;
I do know that there are full Internet hosts in Europe with
X.29 connections: UCL-CS (University College of London)
and NTA-RE (Norvegian Telecommunication Administration - Research
Establishment ?) come to mind. I don't know how approachable they
are. If you have U.S. DoD funding or NATO funding, maybe there
is a TAC you can use ?
The option setting on the X.29 side is fairly complex; there are
about 20 numbered options to fiddle with. I don't think you can
expect them to propagate from the TELNET link. To change X.29
parameters, what you need to do is to set up the link, then
recall your pad (after logging in to CMU or whereever). The means
for doing that are network specifica, and I don't know TRANSPAC.
On TELENET, you can do [return] @ [return]. Then change parameters
with a "set xx:yy" command, and re-connect (with a "continue" command.
In order to have full 8-bit transparency, you must disable pad recall
as part of your option setting.
Hope these thoughts can be of some use to you.
/ Lars Poulsen
Advanced Computer Communications
<Lars @ ACC.ARPA>
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