What are the three phases of congestion control in TCP?

The three phases of congestion control in TCP are slow start, congestion avoidance, and fast recovery. In the slow start phase, the congestion window increases exponentially until it reaches a threshold, allowing the sender to quickly ramp up the transmission rate. During congestion avoidance, the increase in the congestion window becomes linear to prevent overwhelming the network. If packet loss occurs, TCP enters the fast recovery phase, where it retransmits lost packets and adjusts the congestion window to stabilize the connection.