Which of the following statements are TRUE? (S1) TCP handles both congestion…

Answer: S1 and S3 are true; S2 and S4 are false.

• S1 (TCP handles both congestion and flow control): True. TCP implements flow control using the receiver's advertised window (to avoid overwhelming the receiver) and implements congestion control using algorithms such as slow start, congestion avoidance, fast retransmit, and fast recovery (to avoid congesting the network).

• S2 (UDP handles congestion but not flow control): False. UDP is a connectionless transport that does not provide built-in flow control or congestion control; any such behavior must be implemented by the application or other layers.

• S3 (Fast retransmit deals with congestion but not flow control): True. Fast retransmit is a TCP loss-detection mechanism used as part of TCP's congestion-control and loss-recovery strategy. It does not perform flow control (which is handled separately by the receiver window).

• S4 (Slow start mechanism deals with both congestion and flow control): False. Slow start is a congestion-control technique used to probe available network capacity by increasing the congestion window exponentially; it is not a flow-control mechanism and does not manage the receiver's advertised window.

Final selection: choose the option that includes only the true statements S1 and S3.