Networking

BGP

Added: June 15, 2026Nurtured: June 18, 2026

Definition

BGP (Border Gateway Protocol) is the routing protocol used by the internet to exchange routes between Autonomous Systems.

What Problem It Solves

BGP acts as the routing controller of the global internet. It solves the challenge of interconnecting thousands of independent networks (Autonomous Systems) by dynamically discovering the most efficient paths and automatically rerouting around offline nodes.

What Happens If Not Used

Without BGP, the internet would split into isolated networks. Routing paths would have to be manually configured, and a single cable cut in a major backbone would permanently take down large portions of the web.

Easy Wording

BGP decides which road packets should take to travel across the internet.

Layman Example

Suppose you travel:

Faisalabad
↓
Dubai
↓
London
↓
New York

You don't decide. Airlines decide:

Which route exists
Which is fastest
Which is available

BGP does exactly this for internet traffic.

Technical Example

You open:

https://google.com

Browser asks DNS:

google.com
↓
142.250.xx.xx

Now packet starts journey:

Your Laptop
↓
Your Router
↓
ISP
↓
AS100
↓
AS200
↓
Google AS15169
↓
Google Server

BGP helps routers decide:

AS100 -> AS200
or
AS100 -> AS500
or
AS100 -> AS300

Best route gets selected.