>> None of the acks get onto the lan until it is idle, by which time 11
>> are queued and all go out as back to back frames.
> Under what OS?  That's certainly not how the BSD network stack works.
> In BSD, tcp_input() will call tcp_output() when it decides it needs
> to send an ACK, which will transmit the packet immediately.

s/transmit/queue in the driver/.  If the medium is busy, it _can't_
transmit the packet immediately.  Sure, if you're doing full-duplex UTP
to a smart switch, you have no problems.  But there are lots of hubs
and even real co-ax Ethernet networks out there still.

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