What Is Load Balancing?

Load balancing distributes incoming network traffic across backend servers to balance the amount of traffic across a pool of servers. It allows applications to perform better by sending requests to multiple servers, decreasing the burden of managing and maintaining network sessions.

Load balancing allows applications to be readily available to users, boosting performance while also providing an extra layer of security for the network.

How does load balancing work

Load balancing relies on dedicated servers to distribute incoming traffic. The balancer sends requests to servers with the least traffic, requests, or data being distributed.

Sending traffic in different directions allows servers to reliably and efficiently respond to user requests. It also gives companies flexible options to adjust server use depending on the demand for requests from customers trying to access the information.

Types of load balancing

Depending on your needs, you can use different algorithms to help you operate load balancing on a network. The list below shows some common algorithms.

• Round robin: The load balancer delivers requests equally throughout the group of servers. The load balancer sends traffic to servers based on a preset order, so each server receives an equal amount of traffic. This option works best when you expect clients to make similar requests so that it doesn’t overwhelm one server while underutilising another.

• Least connections: The load balancer sends traffic to the server with the fewest current connections. Use this option if you’re unsure of how long a client’s connection with the server will last, prioritising servers with open connections while other servers may still handle client traffic.

• IP hash: The load balancer uses a client’s IP address to determine where to send traffic. This version of load balancing works if you have an organisation that deals with multiple international clients.

• Random: A server at random handles the requests of clients based on an algorithm. You can also choose the random "power of two choices" algorithm, in which the load balancer picks two servers randomly and then chooses the best one to handle the client’s traffic.

Related terms

• Computer networking

• Server maintenance

• IT support

Learn more about load balancing

Load balancing helps optimise performance by managing incoming network traffic across backend servers. It relies on dedicated servers to distribute traffic and can be implemented using algorithms such as round-robin and IP hash. Continue learning about load balancing with the Google IT Support Professional Certificate on Coursera. The certificate programme teaches you the skills you need for an IT support position, including load balancing, troubleshooting computer issues, and day-to-day IT support tasks.