Alibaba Server Load Balancer (SLB) is a fully managed load balancing service that distributes incoming traffic across multiple backend servers (ECS instances, containers, or IP addresses) ensuring high availability and fault tolerance for applications. The service supports both Layer 4 (TCP/UDP transport layer) and Layer 7 (HTTP/HTTPS application layer) load balancing with advanced traffic management features. Layer 4 load balancing provides low-latency, high-throughput distribution for TCP and UDP protocols ideal for databases, gaming servers, and real-time applications. Layer 7 load balancing offers content-based routing, cookie-based session persistence, URL rewriting, and host-based routing for web applications and APIs. The platform provides automatic health checking removing unhealthy backend servers from rotation and adding them back when recovered. SSL/TLS termination offloads encryption overhead from backend servers improving performance. Advanced features include weighted round-robin and least-connections algorithms, connection draining for graceful server shutdown, cross-zone load balancing for multi-AZ deployments, and access logging for traffic analysis. Integration with Alibaba Cloud services enables automatic backend server discovery for ACK clusters, auto-scaling group integration for dynamic server pools, and WAF (Web Application Firewall) for security protection. Performance capabilities include 100 million concurrent connections, 10 million QPS (queries per second), and sub-millisecond response times with intelligent traffic distribution.