The Bluetooth Low Energy (BLE) technology is being used in a wide range of mobile phones, computers, and electronic devices. Consequently, it serves a crucial role in numerous Internet of Things (IoT) applications, providing advantages such as robustness, ease of implementation, low energy consumption, and affordability. However, there are weaknesses associated with this technology, including short transmission range and limitation in terms of the number of connected devices. In 2017, multi-hop communication was added to Bluetooth Low Energy as a new technology named Bluetooth Mesh (BM). The BM technology expanded the communication range and the number of connected devices within a BM network. The BM technology has been a surge of interest in various IoT applications. Within these applications, precise configuration of network parameters is essential, as these settings play a crucial role in the performance of the BM network. Consequently, a thorough examination of this technology’s performance has become essential. To conduct a comprehensive analysis of BM networks, the development of a precise and comprehensive simulator that supports full specifications of BM protocol features is necessary. In this research, a comprehensive simulator, called BMSim, has been designed and implemented for performance eva‎luation of Bluetooth Mesh networks. BMSim supports dynamic adjustment of network parameters, node characteristics and model settings. This run-time reconfigurability enables the simulation of mobile networks and adaptive network settings. BMSim is made available to the research community in an open-source format. To validate its accuracy, simulation results from BMSim were compared with the results of similar real-world experiments conducted using Nordic nRF52840 wireless transceivers. The low deviation observed in these comparisons confirms the capabilities of BMSim to accurately estimate the performance of BM networks. BMSim is then employed to assess the performance of Bluetooth Mesh networks in a variety of scenarios and under different network circumstances. This investigation specifically focuses on the influence of five pivotal protocol parameters: advertising interval, scan window, generation interval, the number of retransmissions in source and relay nodes, and the generation interval of heartbeat messages. In this thesis, mobile Bluetooth mesh networks have been introduced and their performance is examined. The presence of smartphones carried by individuals results in the formation of mobile Bluetooth mesh networks in diverse environments such as streets, homes, workplaces, shopping malls, factories, and hospitals. These networks serve various purposes, including social communication, crowd-sensing, and IoT data collection. While previous research has focused on either fully static BM networks or networks with a limited number of mobile nodes, the performance of mobile Bluetooth mesh networks has remained unexplored. We argue that mobile Bluetooth mesh networks can be a proper networking solution for many applications, thanks to the native support of topology dynamics by the flooding-based end-to-end data delivery of this protocol. This research, presents and eva‎luates the performance of mobile Bluetooth mesh networks and explores the impact of various conditions and parameters on these networks. Additionally, we conduct real-world experiments to demonstrate that mobile Bluetooth mesh networks are feasible and offer relatively good performance. The study specifically investigates three crucial factors: 1) the distinctive characteristics of mobile networks in contrast to static networks, 2) the impact of the ratio of packet generation to advertising intervals on the number of saturated relay nodes, and 3) the influence of retransmissions in both source and relay nodes performance.

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محمدرضا حيدرپور , محمدحسين منشئي , علي بهلولي