## 2 Materials and Methods
### Technical Discussions on Related Works
#### 2.1.1 Wireless Sensor Networks and Challenges
This work had taken the idea of implementing lexicography-based minimum-maximum rate allocation principles, linear rate evaluation programming models and data parametric analysis models to stabilize the overall network lifetime. As the irregular data allocation and data accumulation strategies severely affect each node's performance and lifetime, the entire WSN has been disturbed in its functionality and liveliness. The problem of flexible rate allocation and lifetime stability assurance are considered as the most important issues in WSNs. With this in mind, this work observed the close relationship between individual data rate of each sensor node and the node's lifetime issues during data transmission. The determinations of this existing work had crucial results, yet the need for power stability and channel properties were not considered seriously through MAC and routing cautions. Similarly, [PERSON] et al. [6] prescribed the problems and reliable technical supports for collecting data through underwater sensor networks (wireless channel). As compared to other communication bands such as microwave frequencies and radio frequencies, underwater sensor networks require acoustic signal transmission for data dissemination. The water medium is not free to transmit signals as easily as possible using generic signal bands. Data dissemination through a water medium has many problems relevant to data rate sustainability, packet drops, route breakages, channel reliability and data collisions. The acoustic signals used for multi-hop communication through water become scattered, diverted and attenuated before reaching the destination node. In these situations, the energy spent by each sensor node is not useful. Thus, the need for underwater medium allocation and energy-controlling mechanisms are highly recommended against unequal channel distortions. Particularly, the applications of underwater sensor networks are useful in military-based underwater vehicles and submarine systems. Optimizing the sensor node's resources ensures a long-time data communication through the wireless medium. Especially, the resources of sensor nodes are plunged by both the medium and the malicious activities injected around the network. [PERSON] et al. [7] and [PERSON] et al. [8] expressed the importance of cyber threats and physical layer (channel) threats executed in WSNs. The cyber threats or attacks massively acquire energy resources through unauthorized activities. Particularly, active attacks such as denial of service (DoS) create a major problem for resource availability in WSNs. In contrast, passive attacks such as eavesdropping and wormhole attacks silently gather data dissemination efforts. With this in view, solutions have to be met to ensure stable energy-saving practices against cyber threats. At the same time, counter algorithms to stand against the attacks are expected with energy optimization techniques. [PERSON] et al. [9] and [PERSON] et al. [10] proposed innovative solutions on node coverage and connectivity problems. Among the above contributions, the earlier work developed a unique social spider optimization for improving the sensor node's coverage capability in heterogeneous sensor networks. Each sensor node can transmit the data based on the coverage probability, neighbor availability and neighbor discovery ability. However, the quality of coverage probability and neighbor discovery processes of each node was completely raised based on residual energy level. Generally, various types of technical contributions are motivated to improve the functionalities of the sensor node to attain quality communication. The disparity and the research problems with those works were consistent with inadequate energy optimization views. The second work focused on  
Figure 1: Internal components of sensor node. managing node localization procedures using a cuckoo search algorithm in WSNs. Likewise, a few other research works find solutions against node localization issues [11].