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Internet of Things Prof. M. Cesana Exam– June 26, 2011 Family Name John Given Name Doe Student ID 3030 Course of studies 3030 Total Available time: 2 hours E1 E2 E3 Questions Questions OS 1 – Exercise (8 points) A personal area network (PAN) is composed of 4 motes and a PAN Coordinator. The PAN works in beacon-enabled mode. Ø Mote 1 and Mote 2 require a deterministic communication channel to the PAN Coordinator of 200 [bit/s] Ø Mote 3 requires a deterministic communication channel to the PAN Coordinator of 600 [bit/s] Ø Mote 4 has statistical (non-deterministic) traffic towards the PAN coordinator characterized by the following probability distribution: § P(required rate=0)= 0.2 § P(required rate=100 [bit/s])= 0.2 § P(required rate=400 [bit/s])= 0.6 Assuming that: Ø the active part of the Beacon Interval (BI) is composed of Collision Free Part only Ø the motes use b=100 [byte] packets to communicate with the PANC which fit exactly one slot in the CFP Ø the nominal rate is 250 [kb/s] Ø Mote 1 and Mote 2 are 5[m] away from the PANC Ø Mote 3 and 4 are 10[m] away from the PANC Find 1. The duration of the single slot, the duration of Beacon Interval (BI), 2. A consistent slot assignment for the four motes 3. The duration of the CFP and the duration of the inactive part. 4. The duty cycle 5. The average energy consumption in a BI for a mote of Type 3 if the energy required to operate the TX/RX circuitry is Ec=50 [nJ/bit], the energy required to support sufficient transmission output power Etx(d)= k d2 [nJ/bit], being k=1 [nJ/bit/m2], the energy of being idle in a slot is Eidle = 40 [uJ] and the energy for sleeping is Esleep = 1.5 [uJ] 6. Assuming that the energy budget for the four motes is Ebudget=1 [J], what is the PAN lifetime (number of beacon interval after which the…