The text discusses two types of routing schemes used on the internet: Unicast and Anycast. Under Unicast, every node has a unique IP address, while in Anycast multiple machines can share the same IP address. When a request is sent to an Anycasted IP address, routers direct it to the closest machine. The author explains that CloudFlare uses Anycast for its globally distributed DNS infrastructure, which provides benefits such as speed, resiliency, and attack mitigation.