Cloudflare leverages Linux's networking capabilities, particularly its Netfilter subsystem, to handle billions of requests while mitigating DDoS attacks, and this adaptability was crucial in developing WARP, a mobile-first performance and security app. Facing the challenge of securely and efficiently egressing user packets from edge machines, Cloudflare initially implemented a high-performance VPN using Linux's capabilities, integrating it into their existing network and employing techniques like network address translation (NAT) and conntrack to manage packet flow and security. This setup allowed Cloudflare to route and firewall WARP traffic effectively, though the IPv4 address exhaustion posed scalability challenges, prompting considerations for IP sharing to avoid high leasing costs. The exploration of these solutions and the innovative use of Linux's networking features illustrate Cloudflare's continuous adaptation and development in response to technical challenges, with further insights expected in subsequent explorations.