Steering oceans of content to the world

This post introduces Edge Fabric, a system developed to address limitations in traditional routing protocols like BGP for managing egress traffic at Facebook's Points of Presence (PoPs). Edge Fabric augments BGP with measurement and control mechanisms to overcome its lack of congestion and performance awareness. It collects data on routes, traffic volume, and egress interface capacity. A controller (allocator) projects interface utilization and generates overrides to shift traffic away from overloaded interfaces by injecting BGP updates with high local preference. The BGP Injector service enacts these overrides. The system aims to improve network efficiency and performance by considering factors beyond BGP's static routing decisions.