# An Optimized Hierarchical Cluster Formation Approach for Management of Smart Cities
## 3 Proposed Approach
### Proposed Protocol (ICSI Description)
### Summary of Proposed Work

The ultimate goal of this study is to enhance the cluster formation step for saving power. This goal requires allocating each SN to the optimum cluster, giving a minimum power loss for the CH and the allocated SNs. Three problems guide three questions that result in an optimized approach, with an objective function that is based on three fitness functions with three contributions. Figure 2 depicts the relationship between the research goal, the questions that the current work on ICSI is trying to answer, the research problems, contributions, and the proposed methods. ## 4 Simulation and Results

According to the LEACH protocol, the cluster formation step affects the residual power of numerous nodes, which are candidates to become CHs in other rounds; it might drain the residual energy of many nodes. Therefore, the current research gives this step the ultimate importance for conserving the energy; it is mainly introduced as an optimized version of LEACH that introduces three contributions to compensate for any deficiencies in the cluster formation step. The first contribution is to construct clusters depending on all factors that affect energy consumption instead of considering distance as the only variant that helps conserve network power. The second contribution is to propose an efficient method to evaluate the ability of the residual energy of a node to cover the CEC with all current CHs. The third contribution is the adjustment of the cluster size, according to the residual energy of the CH, to avoid the formation of extra full-size clusters. Since there are few comparable studies that try to enhance or optimize the cluster formation step of LEACH, ICSI has selected the most prominent of them to follow their testing conditions and simulation environment. Therefore, ICSI is compared to I-LEACH-1, proposed by [12]; I-LEACH-2, proposed by [29]; and FBECS, proposed by [33], using two main assessment techniques:

1. The network performance assessment technique, which can be measured using: 1. The first node dead (FND), quarter node dead (QND), and half node dead (HND) in each round. The delayed appearance of the dead node corresponds to a better performing network. 2. Network durability (the number of rounds until all nodes are dead) is employed as another metric for the network performance. Network durability can be estimated by the number of rounds with live nodes. Figure 2: ICSI roadmap. 2. The network survivability assessment technique, which can be measured using: 1. Energy depletion, as another metric for network survivability that measures the consumed energy. 2. The average remaining power of all nodes in the network during each round. 3. The network throughput, which can be measured by successful packet delivery to the BS. ICSI is replicated to certify its performance and durability compared to I-LEACH-1, I-LEACH-2, FBECS, and LEACH. The simulation work is carried out in MATLAB, and it is an edited version from [40; 41]. Two scenarios are considered for the introduced work. In scenario #1, the nodes are equipped with 0.5 J of energy, and the total count of nodes in this scenario is kept at 100 m\({}^{2}\). In scenario #2, the total number of nodes is raised to 200 m\({}^{2}\) with 1 J of energy. For a fair comparison, the values of the simulation parameters for the mentioned related works are retained. Table 3 presents the set of parameters and the baseline settings for the simulation experiment. ### Network Performance Assessment Results

(1) First Node Dead, Quarter Node Dead and Half Node Dead

The percentage of dead nodes is a vital indicator of the non-covered parts of the monitoring area and the consequent performance of the actual system. The performance of ICSI is analyzed and compared to the mentioned related works. As depicted by the bar graph in Figure 3, the traditional LEACH algorithm shows the first dead node in the 200 th round, while the algorithms I-LEACH-1 and I-LEACH-2 show the first dead node in the 300 th round and 280 th round, respectively.