Mac CUSM over a LOCALTALK network - not working!

Geoff Rehn (
Mon, 3 Apr 1995 11:19:06 +0800

Re: Mac CUSM over a LOCALTALK network

Hello everyone.

I have been experimenting with trying to get Macintosh CUSM working over a
LAN, using the built-in LocalTalk networking.

The machines (just two at this stage) are NOT connected to the Internet.
However, I can get them using TCP/IP via choosing LocalTalk in the MacTCP
control panel and having the same HOSTS file in each machine, with dummy IP

Using MacTCP Watcher, all the tests (ping, UDP, TCP) check out OK. I can
use Fetch on one machine to connect to the other running FTPD, so that the
network is in fact using TCP/IP protocols.

However, I cannot get CUSM to work over this little network. After I launch
CUSM, it reports that the other host is not responding when I try and
connect. If I then check the connections with MacTCP Watcher, the
connection has been dropped and I need to reboot both machines.

I can report that I have managed to get the two Macs to use CUSM over a 1-1
ethernet connection (using 10BaseT, and a rewiring of the patch cable!).

I'm using a QuickCam as the video source on just one machine.

Any comments or advice?
I had assumed that CUSM would work over such a simple network, using TCP
over LocalTalk. I am preparing for a paper I am giving soon called "Playing
with TCP/IP: having fun on the InterNet!" and I wanted to be able to show
that schools could "play with" CUSM over a simple local area network such
as the above.

Geoff R.

Geoff Rehn
Lecturer, Educational Technology
Academic Services Unit, Murdoch University