In the slow start phase of the TCP congestion control algorithm, the size of the congestion window

In the slow start phase of the TCP congestion control algorithm, the size of the congestion window increases exponentially. Specifically, the congestion window size starts at a small value, typically one or two segments, and then doubles every round trip time (RTT), as long as acknowledgments continue to be received and no packet loss is detected. This exponential growth occurs because for every acknowledgment received, the congestion window size increases by one segment, effectively doubling the window size each RTT. This exponential increase continues until a packet loss is detected or the congestion window size reaches a threshold value, known as the slow start threshold (ssthresh), at which point the congestion control algorithm transitions from the slow start phase to the congestion avoidance phase.