Free The data link layer lessonsThe data link layer · Stage 1 · Flow control and reliability · Step 2
Sliding windows: go-back-N and selective repeat
Keep several frames in flight, and compare resending everything after a loss with resending only the lost frame. About 15 minutes.
On a link that loses a lot of frames, which protocol wastes the least capacity?
- ASelective repeat, because it resends only the frames that were lost
- BGo-back-N, because its receiver is simpler
- CStop-and-wait, because it has no window
Show the answer
Selective repeat, because it resends only the frames that were lost. Go-back-N resends good frames that happened to follow a loss.
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