TCP retransmission

TCP retransmission refers to the process of resending packets that were not acknowledged by the receiver or were lost in transit. When a sender sends a packet to a receiver over a TCP connection, it waits for an acknowledgment message from the receiver indicating that the packet was received successfully. If the sender does not receive an acknowledgment within a certain timeout period, it assumes that the packet was lost and sends it again. This is known as retransmission.

TCP retransmission is important for ensuring reliable data transfer over the internet. Without retransmission, data packets lost in transit would result in missing data at the receiver end. Retransmission helps to ensure that all packets are received successfully and in the correct order.

However, excessive retransmissions can also be a sign of network congestion or other issues that can affect the performance of the connection. Therefore, it is important to monitor and analyze retransmissions to identify and address any underlying issues that may be causing packet loss.