Which mechanism is used in TCP to dynamically adjust the window size?

The sliding window mechanism is fundamental to the operation of TCP as it allows for dynamic adjustment of the window size based on network conditions. In effect, it determines how much data can be sent before requiring an acknowledgment from the receiver. The primary benefit of the sliding window protocol is that it effectively manages the flow of data, enabling TCP to optimize throughput and ensure reliable delivery without overwhelming the network or the receiver.

As packets are acknowledged by the receiver, the sender can continue to slide the window forward, allowing more data to be transmitted. This adaptive nature ensures that the sender can adjust to varying conditions in the network, making efficient use of available bandwidth.

Furthermore, while slow start and congestion avoidance are critical elements in TCP's congestion control strategy, they are mechanisms that work alongside or complement the sliding window. They help in managing the initial transmission rate and reacting to network congestion, but the actual process of window size adjustment in response to ongoing feedback is encapsulated within the sliding window concept itself.