Lots of IP traffic, no screen activity

Not sure if this is the correct list, but I'll give it a try.  We're trying
to move from M$ to Linux, using Netraverse via X to diskless (or minimal -
like a ThinkNic) workstations.  We're in proof-of-concept mode here, and are
trying to serve this up via the internet to a remote station.  While this
seems to work very speedily over my ethernet connection, it is horribly slow
over an ISDN (here in Texas) ->T1 connection (in Tennessee).  Looking at the
bandwidth, it is generally using about 3K bytes per second, but doing little
to nothing on the remote screen.  Screen refreshes that take a second or so
locally are taking up to 3 MINUTES on the remote, with a constant 3K
bytes/sec of traffic.  Occasionally we see a burst of 10Kbytes/sec, but not
often, and there appears to be no connection with that burst and the rate of
screen refresh.

The way we are doing this is:

ssh -X -f user@localserver <application>

This example came from the Netraverse manual, and, again, it works very
speedily over my ethernetwork, served from the same machine that is giving
it up so slowly.  Is there a better way to do this?  Are there settings to
speed this up?

TIA for answering.

Bill Weaks
Director, MIS
Industrial Molding Corp
806.474.1055
806.474.1168 (fax)