IntServ and DiffServ take opposite approaches. Understanding both helps you choose appropriately.
IntServ:
- Per-flow reservation
- Guaranteed service levels
- High state overhead
- RSVP signaling required
- Best for: Small networks, few flows
DiffServ:
- Per-class treatment
- Relative priority, no guarantees
- Minimal state (DSCP lookup)
- No signaling
- Best for: Large networks, many flows
Hybrid approach: Use DiffServ in the core. Use IntServ at the edge for admission control. Edge routers map flows to DiffServ classes.