service load balancer

A service load balancer is a network component that intelligently distributes incoming client requests across multiple backend servers or service instances to ensure high availability and consistent application performance.

Deployed at layer 4 or layer 7 of the OSI model, the load balancer uses health checks to monitor server status and routing algorithms—such as round-robin or least connections—to direct traffic, automatically removing or rerouting requests from unhealthy nodes. This dynamic routing ensures resilience and fault tolerance for critical services.

Advanced service load balancers support features like session persistence for stateful applications, SSL/TLS termination to offload encryption tasks, and content-based routing using HTTP headers or URL paths. Configuring balancing algorithms, health check thresholds, and security policies carefully is essential to maintain optimal reliability and throughput.