Description: A layer 4 load balancer is a device or service that operates at the transport layer of the OSI model, making routing decisions based on IP addresses and TCP/UDP ports. Its primary function is to distribute network traffic across multiple servers to optimize resource utilization, improve availability, and ensure service continuity. Unlike layer 7 load balancers, which operate at the application layer and can make decisions based on the content of requests, layer 4 load balancers focus on transport layer information, allowing them to handle large volumes of traffic with lower latency. This makes them ideal for applications requiring high performance and low overhead, such as streaming services, online gaming, and critical enterprise applications. Additionally, they can be implemented in both hardware and software, providing flexibility in their use in various environments, including on-premises and cloud settings. In the cloud context, layer 4 load balancers are essential for ensuring that distributed applications operate efficiently and scalably, allowing organizations to adapt to changes in demand without compromising service quality.
