OA. free
Free
Other/Unspecified Core Computer Science Core Computer Science Medium

If N simultaneous Stop-and-Wait ARQ processes run in parallel across independent...

Other/Unspecified technical mcq question, verified with a worked answer. Free to practise - no sign-up.

If $N$ simultaneous Stop-and-Wait ARQ processes run in parallel across independent transmission channels, the aggregate throughput and transmission behavior is equivalent to which protocol?

Choose one option.
Show answer & explanation
Answer: A. Selective Repeat (SR) protocol with window size N

Running N parallel independent Stop-and-Wait instances allows up to N outstanding unacknowledged frames with independent frame-by-frame retransmission, identical to Selective Repeat with window size N.

Step-by-step Derivation:
Step 1: Each independent Stop-and-Wait channel transmits 1 frame and waits for its individual ACK.
Step 2: With N parallel channels, up to N frames can be in transit simultaneously.
Step 3: An unacknowledged frame is retransmitted individually on its channel without affecting the other N-1 frames.
Step 4: This is functionally equivalent to Selective Repeat ARQ with window size N.