Arbitration schemes
Daisy-chain or token passing
- devices either act or pass to next
- fixed priority order
- as many wires as devices
- fairness issues
Centralized
- request to central arbiter
- central arbiter implements priority scheme
- wires from/to each device can be costly
- can be dynamically changing priority/fairness
Distributed
- no central arbiter
- common set of wires (or ether) observed by all devices
- fixed priority/fairness scheme