Consider the 3-way handshaking protocol for TCP connection establishment. Let the three packets exch

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Question

Consider the 3-way handshaking protocol for TCP connection establishment. Let the three packets exchanged during the connection establishment be denoted as P1, P2, and P3, in order. Which of the following option(s) is/are TRUE with respect to TCP header flags that are set in the packets?

Accepted Answer

Correct Answer: (B) and (D)Concept — TCP 3-Way Handshake: Before data transfer begins in TCP, a connection is established using a 3-way handshake. This ensures both sides are ready and agree on initial sequence numbers.PacketSender → ReceiverSYNACKPurposeP1 (SYN)Client → Server10Client initiates connection, proposes sequence number x.P2 (SYN-ACK)Server → Client11Server acknowledges client's SYN (ACK = x+1) and sends its own SYN (seq = y).P3 (ACK)Client → Server01Client acknowledges server's SYN (ACK = y+1). Connection established.Evaluating each option:Option D (P1: SYN=1) — TRUE: P1 is the initial SYN packet from the client. SYN=1, ACK=0.Option B (P2: SYN=1, ACK=1) — TRUE: P2 is the SYN-ACK from the server. Both SYN and ACK flags are set.Option C (P2: SYN=0, ACK=1) — FALSE: P2 has SYN=1 (not 0). The SYN flag is set because the server is also initiating its side of the connection.Option A (P3: SYN=1, ACK=1) — FALSE: P3 is a plain ACK packet from the client. SYN=0, ACK=1. The client does not send SYN again in P3.Reference: Computer Networks — Forouzan / Tanenbaum, TCP Chapter; RFC 793.

Consider the 3-way handshaking protocol for TCP connection establishment. Let the three packets exchanged during the connection establishment be denoted as P1, P2, and P3, in order. Which of the following option(s) is/are TRUE with respect to TCP header flags that are set in the packets?

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More Questions from Transport Layer (Flow Control, Congestion Control, UDP, TCP, Sockets)

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Consider the 3-way handshaking protocol for TCP connection establishment. Let the three packets exchanged during the connection establishment be denoted as P1, P2, and P3, in order. Which of the following option(s) is/are TRUE with respect to TCP header flags that are set in the packets?

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More Questions from Transport Layer (Flow Control, Congestion Control, UDP, TCP, Sockets)

Frequently Asked Questions