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Internet of Things, Exam– July 28, 2015 Total Available time: 2 hours 1 – Exercise (6 points) The Personal Area Network in the figure runs the SPARE MAC protocol where ovals represent reachability between nodes (numbers are mote IDs, letters indicate ovals IDs) with the following parameters: • frame specification: N=10, M=5, • slot specification: duration Ts=8,192[ms], packet length L=128[byte] The slot assignment in the frame is as follows: • Mote 1: slot 1 in the signaling subframe, slot 1 in the data subframe • Mote 2: slot 2 in the signaling subframe, slot 2 and 3 in the data subframe • Mote 3: slot 3 in the signaling subframe, slot 4 in the data subframe • Mote 4: slot 4 in the signaling subframe, slot 5 in the data subframe Find: 1. the nominal data rate and the data rate corresponding to one BCH 2. how many additional motes can be added to the network in the cases the additional motes are added (i) to the overlap region between ovals A and B, and (ii) to the overlap region between ovals B and C; 3. a consistent slot assignment schedule for a new mote 5 entering the network in oval B (the region NON overlapping with ovals A and C) 2 – Exercise (4 points) In the same setting of Exercise 1, assume that Mote 1 and Mote 3 generate unicast traffic directed to Mote 2 according to Poisson point processes with parameters 10 [packets/s] and 4 [packets/s]. What is the average collision probability at Mote 2? 3 – Exercise (6 points) A personal Area Network based on IEEE 802.15.4 beacon enabled mode is deployed to collect temperature samples out of 1000 sensor nodes. Each sensor node collects one temperature sample every 5 minutes and has storage space to store one single sample (if a new sample is acquired and the previous one is still in the local memory, the previous…