Investigation of Node Density Effect on Parent Selection of RPL for Smart Grid

Once the nodes’ workload are concerned, the node density is the critical factor that should be considered comprehensively. In AMI network, the workload of parents should be effectively balanced while concerning the data transmission performance. According to single-parent scheme, the first parent selection – RPL method – cannot meet the high performance of workload balancing ability and it presents poor data transmission performance under long transmission distance. Then, multi-parent solutions, MELT, MAHP and EHPS, are proposed to outperform the demerits of single-parent scheme. However, the effect of node density has not been investigated yet. In this paper, we comprehensively investigate the effect of node density on the performance of RPL, MELT, MAHP and EHPS. As a result, the node density affects the performance of RPL method significantly since it presents poor performance of workload balancing and data transmission. On the other hand, by forwarding small data packets to multi-parents, the node density does not affect the performance of multi-parent solutions since MELT, MAHP and EHPS present high data transmission performance while balance the workload effectively. Moreover, by exploiting merits of single-parent and multi-parent scheme with cognitive radio, EHPS achieves high workload balancing performance and presents the best data transmission performance under long distance.