  In wireless sensor networks (WSNs), designing a stable, low-power routing
protocol is a major challenge because successive changes in links or breakdowns
destabilize the network topology. Therefore, choosing the right route in this
type of network due to resource constraints and their operating environment is
one of the most important challenges in these networks. Therefore, the main
purpose of these networks is to collect appropriate routing information about
the environment around the network sensors while observing the energy
consumption of the sensors. One of the important approaches to reduce energy
consumption in sensor networks is the use of the clustering technique, but in
most clustering methods, only the criterion of the amount of energy of the
cluster or the distance of members to the cluster has been considered.
Therefore, in this paper, a method is presented using the firefly algorithm and
using the four criteria of residual energy, noise rate, number of hops, and
distance. The proposed method called EM-FIREFLY is introduced which selects the
best cluster head with high attractiveness and based on the fitness function
and transfers the data packets through these cluster head to the sink. The
proposed method is evaluated with NS-2 simulator and compared with the
algorithm-PSO and optimal clustering methods. The evaluation results show the
efficiency of the EM-FIREFLY method in maximum relative load and network
lifetime criteria compared to other methods discussed in this article.
