Re: Can HylaFax use terminal server like Xylogics?

["Thomas A. Szybist" <szybist@boxhill.com>]

In message <199706100314.NAA29615@scooby.vic.design.telecom.com.au>, Neil Bucki
ngham writes:
> > Hi,
> > 
> > Possibly a newbie question. Can I setup a HylaFax server that uses a
> > Xylogic terminal server
> > that has fax/modem connected to it? In order to dial out, I telnet to
> > the terminal server at port 7000
> > and issue the AT commands.
> > 
> > Thanks in advance,
> > Kai
> > -- 
> > 
> > Kai O'Yang, PSCIT, Monash U, Australia. mailto://Kai.Oyang@monash.edu.au 
> > URL: http://pscit-www.fcit.monash.edu.au/~oyang     Tel: +61 3 9904 4615
> > ------------------------------------------------------------------------
> 
> 	Not really a answer to your question. But I use a HP terminal server. H
> P has 
> some software ( for HP UNIX maybe some others ) that enables you to access th
> e 
> terminal server ports via device files. I think it also works with some other
>  
> terminal servers so it may be worth a call to HP. Or your UNIX vendor may hav
> e 
> something similar.
> 
> Neil.
> -- 
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> -- Maxwell Smart. Get Smart.
> 
> 
> -- 
> ----------------------------- /-_|\ -----------------------------------
> Neil Buckingham              /     \         5th Floor 360 Elizabeth St
> Telstra                      \_,-._/         Melbourne Australia 3000
> Network Systems                   v          Phone +613 9203 7455
> EMail n.buckingham@vic.design.telecom.com.au Fax +613 9663 8229
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> "A coward is a frightened man who's scared to be brave. But a brave
> man is only a coward who isn't scared to be frightened."
> -- Maxwell Smart. Get Smart.
> 

There are two problems with terminal servers.  The first is network
propagation delays.  There are timing issues all over the T.30 
protocol.  For example the training sequence consists of blasting
a bunch of zero's though the modem at the signalling rate for 1.5
secs.  For a class 1 modem, this would mean the signal would have
to generated at some "host", than transmitted across the network.
No telling what would happen by the time it got there.  Since
much of T.30 protocol is implemented by class 2 and 2.0 modems,
these may work better.

The second problem is all the termios call that HylaFAX makes.
Xylogics as far as I know two mechanisms for associating a 
device file to a terminal server port.  The first is rtelnet.
rtelnet will not work.  If you try to set such things as parity
or baud rate with rtelnet devices, it will simply fail. 
The second method is something they call "terminal server tty".
The idea is that these devices will process changes made 
via ioctls to the device file.  This I think is the only way of
making it work.  I never tried it. I am told by my friendly
Bay Networks representative that this facility is available
only the "Remote Annex".  

That's my understanding.  I reserve the right to be proven wrong.

Tom