What is the Difference Between Flow Control and Congestion Control?

Flow control and congestion control are both traffic controlling methods in computer networks, but they serve different purposes and operate at different levels in the network.

Flow control is an end-to-end mechanism that controls the traffic between a sender and a receiver. It occurs in the data link layer and the transport layer. The main purpose of flow control is to prevent the receiver from being overwhelmed with data. It works by regulating the amount of data that a sender sends. The sender is responsible for the traffic, and it slows down the sender to prevent traffic.

Congestion control, on the other hand, is used by a network to control congestion in the network. It mainly operates at the network and transport layers. The main purpose of congestion control is to prevent the network from being congested. It works by controlling the rate of traffic from the sender to the network. The transport layer is responsible for the traffic, and it slows down the transport layer to prevent traffic.

In summary, both flow control and congestion control regulate the flow of data in a network, prevent packet loss, and improve network efficiency. However, flow control focuses on managing the rate of data transfer between two devices to prevent the receiver from being overwhelmed, while congestion control focuses on managing the rate of data transfer from a sender to the network to prevent network congestion.

Comparative Table: Flow Control vs Congestion Control

Flow control and congestion control are two distinct mechanisms used in computer networking to regulate data transmission. Here is a table highlighting the differences between them:

Flow control primarily focuses on regulating the rate of transmission from the sender's side, ensuring that the receiver does not become overwhelmed by incoming data streams. This mechanism is implemented at the receiver and uses explicit feedback signals from the receiver to the sender.

On the other hand, congestion control is a mechanism used to regulate data flow within the entire network to prevent congestion and packet loss. It is implemented at the sender and uses implicit feedback-based mechanisms, such as the congestion window (cwnd), which dynamically adjusts the speed of data transmission to maintain efficient data rates and prevent network congestion and packet loss. Both mechanisms are vital for maintaining reliable data transfer and improving network efficiency.