The RDT 2.2 protocol (c). Consider the rdt 2.2 sender and receiver below, with FSM transitions labeled in red. Also consider the sender and receiver timeline following the FSMs, where a green OK label indicates a message that is not corrupted, and a red corrupt label indicates a message that is corrupted. We are interested in the sequence number (0 or 1) of a data message, and the ACK number (0 or 1) of an ACK message for the messages sent at t= 2, 3, 4, 5 in the figure below.

Which of the following sequences of interleaved data sequence numbers and ACK numbers corresponds to those in the messages sent at t=2 (data sequence number); t=3 (ACK number), t=4 (data sequence number), and t=5 (ACK number)? Only one sequence is correct.

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		1, 0, 0, 1
		1, 0, 1, 0
		1, 1, 0, 1
		0, 0, 0, 0
		0, 1, 1, 0
		1, 1, 1, 0
		1, 0, 1, 1
		1, 1, 1, 1

SO rdt_send(data) sndpkt-make_pkt(0, data, checksum) udt_send(sndpkt) rdt_rev(revpkt) && (corrupt (revpkt) || iSACK (revpkt,1)) (S1 udt_send(sndpkt) Wait for call o from above Wait for rdt_rev (revpkt) && not corrupt (revpkt) && ISACK(revpkt, 1) A RDT 2.2 sender rdt_rev (revpkt) && notcorrupt (revpkt) && ISACK (revpkt,0) S2 A S5 Wait for ACK 1 Wait for call 1 from above rdt_rev(revpkt) && (corrupt (revpkt) || S4 SACK( revpkt,0)) udt_send(sndpkt) S3 rdt_send(data) sndpkt-make_pkt(1, data, checksum) udt_send(sndpkt) RO rdt_rev (revpkt) && notcorrupt (revpkt) && has_seq0 (revpkt) extract (revpkt, data) deliver_data (data) sndpkt-make_pkt(ACK, 0, checksum) rdt_rev (revpkt) && udt_send(sndpkt) (corrupt (revpkt) | R1 has_seq0(revpkt)) sndpkt-make_pkt(ACK, 0, checksum) udt_send(sndpkt) Wait for RDT 2.2 Wait for O from 1 from below receiver below rdt_rev (revpkt) && (corrupt (revpkt)! has_seql(revpkt)) (R3 sndpkt-make_pkt (ACK, 1, checksum) udt_send (sndpkt) R2 rdt_rev (revpkt) && notcorrupt (revpkt) && has_seql (revpkt) extract (revpkt, data) deliver_data (data) sndpkt=make_pkt(ACK,1, checksum) udt_send(sndpkt) sender receiver t = 0 AK data OK t = 1