generic dialer problems

[Pat Peters]

Background:  We're running Ultrix 2.0 on a MicroVAX II.  We've got Hayes
Smartmodems (1200 baud).  We use the generic dialer of tip and uucp.

Recently, we moved our computers some distance away from their
former location.  Ungermann-Bass NIUs are now used for terminal connectivity.
Phone requests take forever to get done, so we figured on connecting our
modem via a permanent circuit on the NIUs (For those of you not familiar
with the NIUs, the are Ethernet based terminal servers.  The permanent
circuit fixes it so the same two NIU ports always and forever find each 
other and, therefore, the computer and the modem shouldn't know the
NIU is even there).  

Problem:  tip was hanging up the phone the minute the modem connected to
the other side.  Studying the source revealed the cause:  the very moment
that carrier detect is signalled, the generic dialing routines attempt to
read the sync string.  There is NO DELAY before doing the first read.
If there is no character there when the read is done, the dialer aborts.
Apparently the time lag caused by the NIU (so short to be unnoticed by
human terminal users) is long enough to upset the dialer.  I have not
tried the generic dialer in uucp, but it is common code with tip so I
hold little hope it will work better.

Work around:  I've set up the modems as DIR lines instead of ACUs and 
I now talk to the modem myself.  It works, but I prefer to use the dialer--
it instigates a hangup at the end of the conversation instead of sitting
at the mercy of the other end.

Comments?  Suggestions?

Thanks!

-- 
Patrick Peters                 UUCP:    ut-sally!im4u!ti-csl!tifsie!pat 
Texas Instruments                          sun!texsun!ti-csl!tifsie!pat
PO Box 655012  M/S 3635                   uiucdcs!convex!smu!tifsie!pat
Dallas, TX 75265               Voice:   (214)995-2786