# MTRSRP: Joint Design of Multi-Triangular Ring and Self-Routing Protocol for BLE Networks
## 5 Network Performance
### Network Performance of MTRSRP  
To evaluate the network capacity of the three bridging methods in MTRSRP, CORP, and BLEmesh, we measured the data transmission rates to assess the transmission performance. The average data transmission rate was defined as the average number of successfully received data packets per second. We simulated the network data rates for Cases 1, 2, and 3 of the MTRSRP network, CORP, and BLEmesh, and the results are presented in Figure 6. The simulation results showed that the network data rate performance improved as the packet generation rate increased. In the MTRSRP network scheme, we observed that increasing the number of grid links in the inter-ring scatter network led to better data transmission rate performance. Compared to CORP and BLEmesh, the multi-ring network demonstrated superior network data rate performance. This is attributed to the multi-path and self-routing mechanisms in the multi-ring network, which make data packet transmission more efficient than the mesh structure of the CORP and on-demand routing methods, thus effectively increasing the overall network capacity. At peak data rates, the multi-ring network with two inter-ring bridges achieves more than double the data rate of the CORP scheme and 1.6 times the data rate of the BLEmesh scheme. This significant improvement is because the multi-ring network establishes more bridged links within the rings, especially in high-traffic areas, which enables higher data transmission efficiency. A detailed evaluation of the data reception performance for three different configurations, namely MTRSRP, CORP, and BLEmesh, was conducted. The packet delivery percentage (PDP) is defined as the percentage of successfully received data packets in the network compared to all packets generated by nodes. As shown in Figure 7, MTRSRP demonstrates superior PDR performance compared to those of CORP and BLEmesh as the packet generation rate increases. To comprehensively assess the performance of MTRSRP, this study examined three different configurations under varying numbers of network bridges. The results indicate that in the multi-ring network, an increase in the number of bridges and configurations in Case 3 contributed to an improved data reception performance. Specifically, when the packet generation rate was below 8, MTRSRP achieved approximately 100% PDP, indicating its high routing performance efficiency. This superior performance is attributed to the multi-ring network's design involving multiple bridging paths and a self-routing protocol, which significantly enhances the routing efficiency of the network and achieves a higher success rate in packet reception. Figure 6: Average data transmission rate performance of MTRSRP, CORP, and BLEmesh. Figure 7: Average packet delivery percentage performance of MTRSRP, CORP, and BLEmesh. To further explore the load-balancing capabilities of multi-ring networks, this study utilized the packet dropped ratio (PDR) as a key performance metric. The PDR is defined as the ratio of dropped packets to the total generated packets in each network topology. Notably, when the FIFO buffers overflow, the system discards packets, including both currently received and newly generated packets. Figure 8 illustrates a comparison of the PDR performance between the three configurations of the MTRSRP strategy and the CORP and BLEmesh schemes under high-traffic congestion conditions. The results revealed that the PDR of the MTRSRP was significantly lower than those of the CORP and BLEmesh schemes. This is primarily attributed to the uniformity in the node and link connectivity design in the MTRSRP, which allows for a more balanced distribution of network traffic and reduces the PDR. Furthermore, the slope of the PDR performance in MTRSRP was smoother than those in CORP and BLEmesh. This further demonstrates the advantages of multi-ring networks for load balancing.