Design of Congestion Prevention Algorithms in Computer Networks

Vinod Babu Vellank, Suresh Angadi

Abstract: Congestion is said to occur in the network when the resource demands exceed the capacity and packets are lost due to too much queuing in the network. A congestion avoidance scheme allows a network to operate in the region of low delay and high throughput. Such schemes prevent a network from entering the congested state. Congestion avoidance is a prevention mechanism while congestion control is a recovery mechanism. We compare the concept of congestion avoidance with that of flow control and congestion control. We model the network and the user policies for congestion avoidance as a feedback control system. The key components of a generic congestion avoidance scheme are: congestion detection, congestion feedback, feedback selector, signal filter, decision function, and in-crease/decrease algorithms. These components have been explained.

Keywords: Increase decrease algorithms, flow control, congestion control, feedback system