Load Balancing without Load Balancers

This post details Cloudflare's innovative use of Anycast routing at both the Wide Area Network (WAN) and Local Area Network (LAN) levels to achieve load balancing and fault tolerance without relying on traditional hardware load balancers. It explains how Anycast directs traffic to the nearest available data center and how, within a data center, BGP routes are managed by software like Bird to distribute traffic across servers and automatically reroute around failures. The post also touches on early experiments with BGP for more sophisticated load balancing, particularly for protocols like UDP.