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Internet of Things Prof. M. Cesana Exam– June 27, 2013 Family Name Student Given Name Perfect Student ID 30L Course of studies Total Available time: 2 hours E1 E2 E3 Questions Questions OS 1 – Exercise (6 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 100 [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=50 [bit/s])= 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 Ø The 4 motes are out of reach one another Find 1. The duration of the single slot, the duration of Beacon Interval (BI), the duration of the CFP and the duration of the inactive part, a consistent slot assignment for the four motes and the duty cycle. 2. The 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 = 20 [uJ] and the energy for sleeping is Esleep = 5 [nJ]. Assume that the four motes cannot overhear the respective transmissions. 3. Assuming that the energy…