Stop-and-Wait ARQ Algorithm – Explanation and Use Cases

I'm also of the view this is phenomenally unlikely and poses no real problem in any network I know about. So the answer to "commonly-used methods" against it is that there aren't any.

However, you could build a malicious router which would do this: capture (in flight somewhere) a few packets, wait for the sequence numbers to go round, then replay them and we'd trigger this situation. What would happen would depend on the upstairs protocols, which in real life would have to be something like scp or rsync (copy big file) or some streaming service (cctv up for ever?). What else will keep a TCP open for 4GByte? (So perhaps the answer is: "situation is usually prevented because the stream never wraps its sequence numbers because it is too short."

For protocol issues, I note that RFC 7323 "TCP extensions for high performance" covers this exact issue with "PAWS" (protection against wrapped sequences). https://www.rfc-editor.org/rfc/rfc7323#section-5

A quick search shows there's some mention of this in haiku-os and Linux kernel, but I've no knowledge of how much is actually implemented.

Kind regards,

Jonathan.

A probability of 0 doesn't make sense unless you don't want to transfer ever. You need to choose something between 0 and 1.

The algorithm waiting for the start of the slot time reduces the chance that someone else has just started transmitting but the carrier hasn't reached you yet. Overall, it increases the effiency of CSMA by reducing the penalty of a collision.

Not using the first possible slot but working with a probability is way to get a fairer distribution of traffic. It greatly reduces the possibility for a busy sender to hog the medium.

The 1-p probability for the skipping the first slot just expresses that you either send now (probability p) or on the very next slot (probability 1-p). You don't throw the dice for each slot again and again.