networked games 1972 to 1988

der Mouse mouse at Rodents.Montreal.QC.CA
Wed Jun 13 09:01:28 CDT 2007

>> But suppose you have three machines, and connect machine A's 1/2 to
>> machine B's 3/6, B's 1/2 to C's 3/6, and C's 1/2 to A's 3/6.
>> Obviously you'd have to set all interfaces involved half-duplex for
>> it to have any hope of working (so each non-sending host will feed
>> through the signal it gets to the next host in the ring)
> That's not what half-duplex does.  HD doesn't make each interface
> pass on what it receives, it just ensures that nothing is transmitted
> while receiving (or, if it is, that's a collision).

...oh.  I thought half-duplex was basically shared-bus Ethernet - that
all pairs in a collision domain would be carrying the same signal.
Clearly this was more unfounded speculation than reality. :(

Hmm.  I wonder what would happen if you connect A and B's TX pairs and
C's RX pair together, and similarly for B/C TX and A RX, and C/A TX and

Probably nothing (or at least nothing useful).  Oh well.  Annoying; it
looked like a simple "poor man's token ring" setup.

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