What Is Network Congestion?

Date First Published: 31st March 2022

Topic: Computer Networking

Subtopic: Data Transmission Technologies

Computer Terms & Definitions

Difficulty: Easy

Difficulty Level: 3/10

CONTENTS

What Are The Results and Causes Of Network Congestion?
How To Prevent Network Congestion?

Learn more about what network congestion is in this article.

Network congestion is a disruption to the normal flow of traffic to a network, caused by it receiving more traffic than it can handle and exceeding its maximum capacity. Congestion is often a temporary issue related to excessive traffic in the network, but persistent network congestion indicates more serious issues, such as DDoS attacks.

What Are The Results and Causes Of Network Congestion?

Network congestion results in:

Much slower response time. Response time is the time that it takes for a system to respond to a given input. Network congestion will greatly slow the response time and cause the network to become less responsive to requests.
Data packet loss. Network congestion will cause a lot of data packets to not reach their final destination. Eventually, they will be lost due to a timeout.
Reduced QoS.
Increased levels of latency.

The causes of network congestion are:

Too many devices requesting network access. The more devices that are connected to a network, the slower the network will be. This is because lots of devices requesting network access forces the network to work harder in order for the devices to connect. When there are excessive numbers of devices requesting network access, the network cannot handle the requests for data.
DDoS attacks - These cause network congestion because of the network being overloaded with malicious traffic. These can cause disruption to networks on a continuous basis and cause it to become unresponsive.
Incompatible hardware. For example, different categories of Ethernet cables have different maximum speeds. When Ethernet cables are unable to handle the speed the network requires, this will greatly slow down the network.
Poor network design. Larger networks are usually divided into subnets for better performance. If the subnets were not scaled in accordance with the usage patterns and resource requirements, network congestion could happen.
Maintenance. There are times when the network will temporarily get congested because of maintenance by the ISP, such as upgrading network capacity.

How To Prevent Network Congestion?

Network congestion can be prevented by the following ways:

Monitoring network traffic - Network congestion can be monitored by taking a look at the times of day when network traffic is high. In businesses, network discovery tools can be used to find that out. Network discovery tools work by scanning all of the virtual networks, cloud servers, and other wireless networks and devices, which identifies the users and devices that use up the most traffic. Inefficient devices can contribute to network congestion.
Prioritising network traffic - When network traffic is prioritised, bandwidth is reserved for certain users, devices, and processes. Certain non-essential devices will be slowed down and processes that use up a large amount of traffic can be scheduled to take place when the network is not in use.
Increasing bandwidth - Increasing bandwidth will mean that the network will be able to handle more traffic, resulting in faster connection speeds and reduced network congestion. In most cases, bandwidth can only be increased by the ISP and will result in additional charges.