Networking
Advanced
What is BGP (Border Gateway Protocol)?
The routing protocol that makes the internet work by exchanging routing information between autonomous systems.
BGP is the protocol that connects different networks (ISPs, cloud providers, enterprises) on the internet. Each network (Autonomous System) announces its IP prefixes to neighbors, building a global routing table. BGP chooses paths based on policies, not just shortest distance.
BGP is a path-vector protocol that prevents loops by tracking the full AS path. Misconfigurations can cause route leaks (redirecting traffic) or route hijacks (advertising someone else's IPs). BGP is critical infrastructure — incidents can affect internet connectivity globally.
