Cloudflare architecture and how BPF eats the world

This post details Cloudflare's extensive use of eBPF (extended Berkeley Packet Filter) within its Linux-based edge network infrastructure. It highlights how eBPF is employed for critical functions such as volumetric DoS mitigation (XDP eBPF), layer 4 load balancing (XDP eBPF), and sophisticated socket filtering for UDP traffic. The post also touches upon custom kernel patches and iptables modules (TPROXY) used to overcome Linux networking limitations for advanced dispatching and handling of high volumes of traffic, showcasing a deep dive into kernel-level optimizations for network performance and security.