Glossary

Review the definitions for terms used across Cloudflare's BYOIP documentation.

Term	Definition
address map	A data structure enabling customers with BYOIP prefixes or account-level static IPs to specify which IP addresses should be mapped to DNS records when they are proxied through Cloudflare.
autonomous system numbers (ASNs)	A large network or group of networks that has a unified routing policy. Every computer or device that connects to the Internet is connected to an autonomous system.
Border Gateway Protocol (BGP)	The routing protocol for the Internet, which is responsible for picking the most efficient routes to deliver Internet traffic.
Internet Routing Registry (IRR)	A globally distributed database of routing information which contains announced routes and routing policies in a common format. Network operators use this information to configure backbone routers.
Resource Public Key Infrastructure (RPKI)	A cryptographic method of signing records that associate a route with an originating autonomous system number.
Route Origin Authorization (ROA)	The RPKI-signed object that states an autonomous system is authorized to originate a particular IP address prefix or set of prefixes.
Unicast Reverse Path Forwarding (uRPF)	A security feature that can prevent spoofing attacks.