In the amateur radio world, AX.25 "packet radio" terminal node controllers supported KISS mode, which left the CSMA and HDLC framing in the TNC but offloaded the state-machine for connection management to the host CPU stack.
KISS merely provided a way to forward the frame metadata and payload over the serial link between the TNC and the host. With buffering at each end of the serial link to the TNC, knowing exactly when a specific frame of data has been transmitted on air is impossible and this causes some grief in the Linux kernel's internal implementation of the state machines for connected mode AX.25, specifically when scheduling retransmissions. To be fair, we are talking about fairly large buffers and fairly low bit-rates on tx here - 1200 baud typically, but nugatory retransmission due to channel state backoff without backpressure is a bugger. I assume that we would want a control plane that can provide that kind of feedback, and would want some way of tagging transmission data units as requiring some kind of notification of transmission on-air. I'm very new in the gr world so can't talk with authority on anything other than provide vague waffle such as this for your consideration. Cheers, Darren, G0HWW _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio