Explain the principle of operation and purpose of load balancers in systems.

A load balancer is a component that distributes incoming traffic or requests among multiple servers or resources to ensure:

• Even distribution of load and avoidance of overload on individual servers.
• Increased fault tolerance and system availability.
• Improved performance through parallel processing of requests.

Principle of operation:

1. The load balancer receives incoming requests.
2. Based on the selected algorithm (e.g., round-robin, least connections, IP-hash), it directs the request to one of the available servers.
3. It monitors the status of servers and excludes unavailable ones from the pool.

Example: In a web application, the load balancer distributes HTTP requests among several web servers to ensure stable operation with a large number of users.