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Internet of Things, September 8, 2015 Available time: 2h Exercise 1 (4 points) A multi-hop ZigBee personal area network (PAN) is characterized by the following topological parameters: number of ZigBee routers per tree level r=2, number of ZigBee end devices per tree level d=3, number of tree levels L=2 (The PAN coordinator plus two more levels). Plot a graph representing the network and assign network addresses to all the network devices according to the ZigBee address assignment rules. Exercise 2 (6 points) A Personal Area Network composed of 50 motes and a PAN Coordinator is operated according to the IEEE 802.15.4 beacon enabled mode with the following parameters: • Active part composed of CFP only (no CAP) with slots of 128 [byte] packets; • Nominal data rate is 250 [kbit/s]; • 20 motes of Type 1 generate uplink traffic whose rate follows this with the following distribution: P(r=25[bit/s])=0.4 P(r=50[bit/s])=0.6 • 30 motes of Type 2 generate uplink traffic whose rate follows the distribution: P(r=50[bit/s])=0.2 P(r=1[kbit/s])=0.8 Define a consistent Beacon Interval structure including the number of slots in the CFP, the Beacon Interval duration, and the duty cycle. Define a consistent slot assignment in the CFP for all the devices in the network. Write the average energy consumption for motes of Type 1 and 2 in case all the motes are in radio range (let Erx=40[mJ] be the energy per slot for receiving/overhearing transmissions, and Eidle=20[mJ] and Esleep=10[uJ] the energy per slot for being idle and sleeping). Exercise 3 (6 points) A sensor node generates a stream of 3 packets at a fixed rate of one packet every x [s]. The packets must be delivered to a sink node for further processing. The nominal data rate is R=250[kb/s] and the packets are of L=1000[bit]. The…