## 1 Introduction
The simulation results showed that the proposed protocol performed better than E-DEEC in terms of throughputs, residual energy, and network lifetime. [PERSON], in [28], explained an extended form of Threshold Stable Election Protocol called eTSEP. The new scheme introduces the distance and residual energy into the election probabilities of each level of the nodes. This allows nodes with high residual energy and closer to the Base station to stand a better chance of becoming a cluster head. The performance of the scheme was evaluated using MATLAB R2017a and compared with TSEP. It has been shown that the new protocol performed better than TSEP in terms of throughputs, residual energy, and the network lifetime. However, the single-hop communication technique is used in data transmission from the CHs to the BS. This depletes the energy of the distant nodes. A heterogeneous form of Modified Low Energy Adaptive Clustering Hierarchy, Servant-MODELACH (S-MODELACH), was presented in [29]. The algorism uses three levels of nodes, namely advanced, servant, and normal nodes. The protocol chooses cluster heads based on their residual energy and assigned data aggregation role to a group of nodes called servant nodes. It has been shown that S-MODELACH achieved better outcomes than MODELACH in respect of throughputs and the network lifetime. Although the scheme used a multi-hop communication approach to reduce the energy depletion of the distant nodes, no mechanism was put in place to reduce energy holes created in the network. An enhanced form of Threshold Distributed Energy Efficient Clustering protocol (TDEEC) has been proposed in [30]. The algorithm, Gateway based-TDEEC, introduced a gateway node at the middle of the sensing area and then installed the BS far away from the sensing field. The cluster heads relay their data to the gateway which will then aggregate the data and send the final report to the BS. Results showed that the proposed protocol outperformed the TDEEC in terms of stability period, throughput, residual energy, and network lifetime. However, it did not consider a multi-hop communication strategy to reduce the energy expenditure of the distant nodes as well as reducing the energy holes created in the system. A modified heterogeneous routing protocol called Distance-DEEC (D-DEEC) has been proposed in [31]. The protocol took into consideration the residual energy, distance of the individual nodes, and average distance of all the nodes from the base station in selecting the cluster heads. This has allowed the scheme to select cluster heads with high residual energy, closer to the Base station and their neighbors. The performance of the proposed algorithm was evaluated using MATLAB R2017a, and the outcomes showed that the D-DEEC protocol outperformed DEEC in terms of energy consumption, throughputs, and the network lifetime. In [25], the author proposed TEEN-MGEAR(T-MGEAR). The scheme modified the election probability by considering the distance and the residual energy of the nodes in selecting the cluster heads. It also employed hard and soft thresholds to determine when nodes can transmit their sensed data. No heterogeneity and multi-hop communication technique has been employed in this scheme. In [32], an Enhanced M-Gear Protocol for Lifetime Enhancement in Wireless Clustering System was proposed. In this scheme, the network was divided into a number of sections with each section having its own gateway node. The nodes capture data and transmit them to the gateway in their immediate section for onward submission to the next gateway or to the BS. The results showed that it outperforms MGEAR in terms of throughput, energy consumption, and network lifetime. However, having several gateways will lead to an increase in the cost of the network; also, the absence of heterogeneous nodes affects the stability period of the network. The authors in [33] explained a Gateway-Stable Election Protocol (G-SEP).