Internet Exchange Points (IXPs)
💡 The Core Idea
An IXP is a physical infrastructure (often a switch in a data center) where multiple networks meet to exchange traffic directly, bypassing upstream providers.
🧠Evolution & Peering
- Bilateral Peering: Two networks run a direct cable and BGP session. Hard to scale.
- Multilateral Peering (Route Servers): Networks connect to a central Route Server (RS). The RS collects routes and redistributes them, allowing an AS to peer with 50+ networks via a single BGP session.
Benefits
- Keeps local traffic local (lower latency).
- Reduces costs (less traffic sent to paid transit providers).
- Can provide DDoS mitigation (Blackholing).