At IXPs, many networks connect. Without help, each needs BGP sessions with all others.
The problem: An IXP with members needs bilateral sessions.
Route servers solve this: A route server collects routes from all members and redistributes them. Each member needs only or sessions.
How they work:
- Members peer with the route server
- Route server runs BGP but doesn't forward traffic
- Routes pass through with NEXT_HOP preserved
- Traffic flows directly between members