> I have been experimenting with altering the frame loss and corruption rates of stopandwait and piggyback, and have found stopandwait always sends at a higher rate. As I understand it, this because stopandwait is sending acknowledgement frames without data.
> So, does this mean the 2 line graph is not demonstrating the efficiency of the protocols in terms of rates of data sent?
Have a peek at the sample solution which, I believe, explains this:
"Remember why we are considering piggybacking - to reduce the number of frames crossing the Physical Layer and,
thus, to reduce the number of hardware interrupts managed by each node's operating system.
Because the piggyback protocol introduces an artificial delay, waiting for an outgoing data-frame to carry each
acknowledgment, the rate of progress of the protocol is necessarily slower and will transmit fewer Application Layer messages."