TCP Congestion Avoidance Configuration on 300 Series Managed Switches

Objective

Congestion of a network node takes place when the input of the node is higher than the output. When a sender node notices the congestion of a remote node, the sender uses a slow start algorithm. Slow start is a mechanism that is used to control the transmission rate of a node. This rate is determined by the return rate of acknowledgements from the receiver. When multiple sender nodes use the slow start algorithm, they tend to synchronize sending rates, which leads to inefficient use of bandwidth. To avoid this problem, known as TCP global synchronization, TCP Congestion Avoidance is used. TCP Congestion Avoidance slows the transmission window by one half. This is used in conjunction with slow start so that the transmission rate runs at an optimal pace.

This article explains how to enable TCP Congestion Avoidance on the 300 Series Managed Switches.

Applicable Devices

• SF/SG 300 Series Managed Switches

Software Version

• 1.3.0.62

TCP Congestion Avoidance

Step 1. Log in to the web configuration utility and choose Quality of Service > General > TCP Congestion Avoidance. The TCP Congestion Avoidance page opens:

Step 2. Check the Enable check box in the TCP Congestion Avoidance field.

Step 3. Click Apply. The Enable TCP Congestion Avoidance window appears.

Step 4. Click OK. TCP Congestion Avoidance is enabled.