networking & internet

What Is Load Balancing And How Does It Work?

What is load balancing?

Load balancing is the process of distributing network traffic across multiple servers. This ensures no single server bears too much demand. By spreading the work evenly, load balancing improves application responsiveness. It also increases the availability of applications and websites for users.

How does load balancer work?

A load balancer routes the client request across all servers to increase speed and capacity. This ensures that no server is overworked and in this way maintains the system performance. Upon failure of a server, the load balancer will stop directing traffic to that server. Simply put, the load balancer is like the traffic controller who is guiding the cars on the road. The cars will be guided in such a way so that there is no traffic congestion and closed roads will not be used. A smooth flow of traffic and even distribution of cars will be ensured on all the roads.

However, the load balancer is generally programmed to direct traffic through specific links. This means no matter the amount of traffic, it will be directed through the same link. It cannot monitor the route congestion and direct accordingly. This may create an imbalance in the amount of data transmitted in each link, and may result in certain connections being overworked. This will create a bad network experience. Furthermore, when one link goes down traffic through that link is stopped completely, it is not routed to other available links.