[ih] uucp, was Question re rate of growth of the Arpanet

[Lyndon Nerenberg (VE7TFX/VE6BBM)]

> the Telebit modems ran at 19.2 and had some "magic" in them called
> "UUCP Spoofing" that IIRC "faked spoofed" the UUCP ACK packet locally
> at the forward sending host to make it run lickity split rather
> than having to "endure" the latency of remote receiving host sending
> it back.

The telebits took advantage of the half duplex nature of the UUCP
'g' prototol.  When sending a->b, the modems would configure the
line for bulk data transfer in the a->b dirction.  The a modem
would then directly speak the 'g' protocol with the local host
(pretending to be the remote node), block the data into an internal
buffer, then send the buffered data across the link (possible
conpressed?).  At the other end the reverse set of steps would take
place.  When the a node exhausted its file send queue, the modems
would reverse the line and file transfers from b->a would happen.

--lyndon