The distributed mechanism of LEACH algorithm is used for cluster formation and cluster head selection, it may result in poor cluster structure in which some clusters contain a much larger number of nodes than others do. Furthermore, randomly choosing CHs lead to the fact that there is a high chance for one node to be a CH during several rounds of operation, this node consumes more energy and may die out within a short period of time. Clustering with One-Time Setup (COTS) is an improvement of Low-Energy Adaptive Clustering Hierarchy (LEACH) is used by removing the cluster-reforming process and adding a rescheduling slot to the end of every round energy is significantly saved.