Each protocol handles scale differently:
RIP:
- Hard limit: hops
- Practical limit: - routes
- Bottleneck: Full table broadcasts every seconds
OSPF:
- Soft limit: - routers per area
- Practical: Thousands of routers with proper area design
- Bottleneck: SPF calculation complexity, LSA flooding
EIGRP:
- No fixed limits
- Practical: Hundreds of routers per autonomous system
- Bottleneck: Query scope, SIA events
OSPF scales best for large networks with proper hierarchy. EIGRP works well for medium networks. RIP doesn't scale.