The CBX
The IBM 9751 Computerized Branch Exchange (CBX) provides voice and data
services to the Virginia Tech campus. Your data phone, probably a ROLMphone
120, provides a data LAN capable of speeds up to 19.2 Kbps. To see how your
ROLMphone is configured start a communications package such as Kermit or TinCan
and enter
display characteristics or simply d c
Except in rare cases, you do not need to change these settings as the CBX is
able to adapt to the settings of your communications package.
Physical Arrangement
There are 6 CBX switches: Hillcrest, Burruss, Shanks, Owens, Cassell and one
at the Corporate Research Park. Both data and voice calls within a service
area stay within the area. Calls outside the local area's range are routed
based on the least amount of traffic.
Using the CBX
To use the CBX, you will need a communications package such as Kermit or
TinCan. Start the package. You should configure the software based on the
system to you wish to log on to. 7 data bits, one stop bit, and parity space
or none should work for something like DROPADD. Most other systems work with 8
data bits, one stop bit, and parity none but experiment if you have problems.
Once you have your computer connected to the ROLMphone,and the power supply
attached, you should be able to start your communications package and press
return to see the CALL, DISPLAY OR MODIFY? message.
You can either call one of the listed groups (enter d g to see available
ones) or dial a campus or off campus data service. For on campus services,
just dial the 5 digit voice phone number. The CBX realizes it is a data call
and looks for a server computer at the other end.
For off campus access, dial a 3 and the phone number. You will be asked for a
long distance authorization code. If the call is to a local number, 9 and the phone number should work just fine.
