: | The first time I heard the term 'SPOOFING', I tough that was a joke! it
: | come from a Telebit
: | technical support member.
: AH! Quite another story. Of course, Telebit modems spoofed the uucp
: protocol. It took in bytes from the sending machine, and ackowledged them
: AS IF it were the receiving uucico that was talking. It then transmitted
: the bytes using Telebit's proprietary PEP protocol, and on the other end,
: the receiving uucico thought it was listeneing to the sending uucico, but
: it wasn't, it was the receiving modem that was pretending to be a uucico.
: Certainly it was spoofing. Of the uucp protocol, not of any baud or speed.
Yep. A little detail. Telebit modems had to spoof any protocol
that required an acknowledgement or it would run no faster than
about 2Kbps. This is because the PEP protocol had a guaranteed
140msec turn around delay. PEP uses all the bandwidth available
in one direction with a small reverse channel. (Actually 512 channels
of 20bits/sec each). To transmit an ACK or NACK for a file transfer,
the modem had to flush all those channels, and convince the DSP to
do it all in the other direction. The various PEP modems could
also spoof Xmodem, Ymodem, Kermit and UUCP.
Somewhat later, Mulitech introduced spoofing in their MT932 and
MT1432 modems. I never could get it to work right, even between
two identical Multitechs. However, full duplex (using adaptive
equalizers and echo canceller technology) in V.32 and V.32bis
modems that resulted in the total elimination of the turn around
delay problem, also eliminated the necessity to spoof the
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# Jeff Liebermann Liebermann Design 150 Felker St #D Santa Cruz CA 95060
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