However. Link utilization 30% >70%time is idle but inter face is power on 80 60 95 20 01503004506007509001050120013501500 Time (seconds) cation Networks
Communication Networks However, Link Utilization < 30% • > 70% time is idle but interface is power on
10GBase-T Energy Efficient Ethernet IEEE 802.3az: interfaces go to sleep when IdlE frame departure Low Power Idle (LPD frame arrival Counter: 1 Counter: N Timer 0 or Timer: it 100% cation Networks
Communication Networks 10GBase-T Energy Efficient Ethernet • IEEE 802.3az: interfaces go to sleep when IDLE
Role of Two thresholds Timer t bounds the delay when traffic load is low Timer expires first Low Power Idle (LPD) Counter n bounds the queue length when traffic load is high Counter expires first ≌ Low Power Idle/s (LPD) ommunication Networks
Communication Networks Role of Two Thresholds
Sleeping Strategies I&n policy: T and n are finite t policy:N→∞ N policy:τ→∞ ommunication Networks
Communication Networks Sleeping Strategies
Problem Tradeoff between power efficiency and delay N and T↑→ LPI Length↑ power efficiency↑ average delay↑ Example: 86% power is wasted for overheads ifN=1 Q乐 100 10% Our goal: what are the rules to select N and t? ommunication Networks
Communication Networks Problem