2021 Volume 11 Issue 2 Pages 492-515
Currently, research on Bluetooth-based mobile ad hoc networks (hereinafter referred to as Bluetooth MANETs) is being conducted. As an application of Bluetooth MANETs, a grass-root disaster information propagation system has been studied for the purpose of information distribution following disasters. Bluetooth standards include Classic Bluetooth (hereinafter referred to as Classic), which can transfer relatively large data packets, and Bluetooth Low Energy (hereinafter referred to as BLE), which can work with relatively low power consumption. So far, a rapid connection establishment method that combines Classic and BLE in a complementary manner (hereinafter referred to as the existing method) and the flooding-based data packet transfer method with delay- and disruption- tolerance have been proposed. In the existing method, a Bluetooth MANET is constructed by connecting multiple piconets, which consist of one master and multiple slaves. In the existing method, loops are easily formed in a Bluetooth MANET due to the establishment of connections between slave terminals in a piconet in an environment with high terminal density. Therefore, when the flooding-based data packet transfer method is used in the existing method, the amount of data packets increases and the processing load on the terminals increases. In this paper, we proposed a method to reduce the number of loops by controlling the connection establishment between slave terminals in a piconet for Bluetooth MANETs (hereinafter referred to as our proposed method). In addition, we have evaluated the effect of our proposed method on data packet transfer through simulation experiments. As a result, we confirmed that our proposed method can reduce the number of loops and the number of data packet transmissions while maintaining the time to complete the data packet dissemination at the same level as the existing method.