Load Balancer

Load Balancer
Overview

A load balancer is a device that distributes network traffic across multiple servers to ensure no single server becomes overwhelmed with too much traffic. It typically operates at Layer 4 (Transport Layer) or Layer 7 (Application Layer) of the OSI model.

Key Functions
  • Distributes incoming network traffic across multiple servers
  • Improves application responsiveness and availability
  • Prevents any single server from becoming a single point of failure
  • Can perform health checks on servers to ensure they can handle requests
  • May provide additional features like SSL offloading and content-based routing
OSI Model Layers

Load balancers typically operate at Layer 4 (Transport Layer) or Layer 7 (Application Layer) of the OSI model. Layer 4 load balancers make routing decisions based on IP addresses and TCP/UDP port numbers, while Layer 7 load balancers can make decisions based on the content of the application data.