How does load balancing work in a distributed web environment?

Load balancing in a distributed web environment works by distributing network traffic across multiple servers to ensure no single server becomes overwhelmed.

In a distributed web environment, load balancing is a critical aspect that ensures the efficient distribution of network traffic across multiple servers. This is done to prevent any single server from getting overwhelmed, which could potentially lead to slower response times or server failure. The main goal of load balancing is to optimise resource use, maximise throughput, minimise response time, and avoid overload of any single resource.

Load balancing can be achieved through various methods, but the most common one is round-robin scheduling. In this method, each request is sent to the next server in line, cycling through all the servers in the system. This method is simple and easy to implement, but it doesn't take into account the current load of each server, which could lead to uneven distribution if some servers are more powerful or less busy than others.

To address this issue, more sophisticated load balancing algorithms have been developed. These include least connections, where requests are sent to the server with the fewest active connections, and least response time, where requests are sent to the server that is expected to respond the fastest. These methods require more complex monitoring and decision-making systems, but they can result in a more evenly distributed load.

Another important aspect of load balancing in a distributed web environment is session persistence, also known as sticky sessions. This is a method used to ensure that a user's interactions with a website are handled by the same server for the duration of the session. This is important for applications where data is stored in memory on the server, such as shopping carts on e-commerce sites.

In conclusion, load balancing is a crucial component in a distributed web environment. It ensures that network traffic is evenly distributed across multiple servers, preventing any single server from becoming overwhelmed. This results in improved response times, maximised throughput, and optimised resource use.