Re: Ethernet Modems

["Terry Olsen" <tolsen64@hotmail.com>]

> Are you sure you're not just running into the problem that file
> transfer protocols like X/Y/Z modem don't work particularly well over
> TCP/IP connections?  I remember doing file transfers with Spectrum
> over a dial-up TCP/IP connection to Delphi (back when they still had a
> text interface) and the file transfers were very slow, had to have
> quite a number of retries and would sometimes even fail.  I seem to
> recall others having even less success than I did.
>
> I believe it comes down to the timeouts that the X/Y/Z modem protocols
> use and the fact that TCP/IP won't necessarily get the next packet to
> your communications program within that time.  This can be partly
> explained due to the fact that TCP/IP doesn't need to send things in a
> consecutive manner.  A simplified example:  you could receive a TCP/IP
> packet with block 2 of an Xmodem transfer before you receive the
> TCP/IP packet with block 1 for instance but your communications
> program won't receive anything until the TCP/IP packet with block 1
> arrives.
>
> It seems strange to me that programs or hardware would purposely limit
> themselves to only working with 7 bit characters instead of 8 bit.
>

I'm not sure about all that...but the BBS at tloc.antsinthepants.com port 
9999 is running off the serial port on a Cisco router, and I haven't had any 
problems at all transferring files back & forth...