This article discusses problems with connecting Macintoshes to Wang VS
processors. The client is currently doing terminal emulation and file
transfer on local and remote Wang VS processors. After some
experimentation, they have attached a NetSerial modem to their AppleTalk
network (using LocalTalk) with a customized version of VS Term. They are
connected to the Wang VS through a WACS controller and use the RS-232 cable
(19.2 bps) to attach to the NetSerial.
This solution is too slow for them, particularly when doing file transfers.
The slowness in the network is due not to LocalTalk (LocalTalk
transmissions are 230.4K bits-per-second), but to the RS-232 connection
running at 19.2K bits-per-second. This means the RS-232 segment of your
connection to the Wang is running 12 times slower than the LocalTalk.
There might be a way to connect Macintoshes to the Wang via Ethernet, but
there are some prerequisites. NCSA Telnet from the University of Illinois'
National Center for Supercomputer Applications, or NetOne from
Ungermann-Bass, must be used on the Macintosh to make a VT100-emulation
connection through TCP/IP and FTP communications. These packages are
compatible with LocalTalk or EtherTalk for the Macintosh.
Connecting the Macintoshes to the Wang Ethernet is fairly straightforward
using Kinetics FastPaths, Cayman GatorBoxes, Apple EtherTalk cards, or any
of the various Macintosh Ethernet connectivity units from Kinetics.
The difficulties are with the Wang system, itself. The following questions
must be resolved before the above solution can be implemented:
1) Does the Wang VS system use TCP/IP and FTP? If it uses WangNet, then
these communication protocols will not work.
2) Can terminals be connected through the Ethernet? Some office systems
may implement Ethernet for file transfers only and have no facilities
for handling remote terminal connections across the Ethernet.