Fig. 5
From: Hybrid energy-efficient APTEEN protocol based on ant colony algorithm in wireless sensor network
Flow of the AMAPTEEN protocol. The generated random number is compared with the formula threshold to determine CH. The non-CH node selects the CH with the strongest received signal to join and become the cluster’s CM. Nodes are divided dynamically into several clusters. A virtual link between the CH and the CMs is established. CH selects the CM node with the largest pheromone concentration on the link as IM_node. The IM_node is chosen by CH whenever there are data transmitted from CH to sink node. CM sends the sensed data to CH in its allocated TDMA slot. When CH receives the data from all the CMs, it collects and aggregates data and sends the merging message to IM_node. The IM_node forwards the message to far sink node. The choice of IM_node depends on node maximal pheromone concentration, and thus, choosing the data transmission path is relatively optimal. And it is likely to be different, so there will be formed multiple data transfer paths from CH to sink