[comp.protocols.misc] Question about YMODEM G protocol over an Annex Terminal server line.

fuhrman@b.coe.wvu.wvnet.edu (Cris Fuhrman) (08/30/89)

Hi.

I have a Courier HST modem attached to a port on an Annex I terminal server.
The idea is to allow several different people access to a high-speed modem.

Connecting to various bulletin boards across the country is possible, but
there seems to be a problem with some of the download protocols (on a PC 
compatible running TELIX or ProComm Plus), particularly YMODEM-G protocol.

It appears that the Annex connection to the modem is getting 
stuck when the Ymodem-G file transfer begins.  It is possible to reproduce
these transfers successfully without the Annex as an intermediate connection.
Also, other protocols, like Kermit and XModem, seem to work ok either way 
(through the annex or just directly).

Is it possible that a control character coming down the line into the Annex
is locking it up?  What are the parameters that I should change on the
Annex port to enable all characters coming down the line to pass through
without locking up the port?  What is it about YMODEM-G that makes it so
different from the other protocols as far as control characters?

By the way, here's the scheme of how a user would access the modem:

He starts up PROCOMM on a PC connected via serial port to an Annex line.  
At the annex: prompt, the user types 'telnet annex3' where annex3 is the
annex with the modem connected.  He then presses return, and then types
the port number of the modem.  At this point, he is connected to the HST
modem, and may dial up a bulletin board, connect to it, and download files.

Please respond via e-mail to manager@a.coe.wvu.wvnet.edu

Thanks,

-Cris Fuhrman
 WVU College of Engineering