Border Gateway Protocol (BGP) is the core routing protocol that glues the Internet together and allows Autonomous Systems (AS) to figure out how to transmit a packet from its source to the destination, potentially traversing multiple intermediate ASes along the way. BGP routing works on a path vector basis - ASes inform their neighbours of the routes they know how to reach, and this information propagates across the Internet.
BGP allows ASes to:
- Find the best route As data travels across the internet from source to destination, every autonomous system in between has to decide where the data packet should go next.
- Discover network connection changes The structure of the internet is dynamic. New autonomous systems are being added, and old ones are being removed constantly.
- Administer network policies BGP has the flexibility to allow autonomous system administrators to implement their own routing policies.
- Add a layer of network security BGP supports security in your network management.
Sources
- Why the Internet Is Both Robust and Fragile, ByteByteGo NewsLetter
- What is BGP?, AWS Documentation