## Relevant Contributions Related to Sensor Placement
### Relevant Contributions Related to Routing Algorithms  
In addition to sensor network deployment and location, routing is another one of the most noticeable research challenges in WSN that has gained much ground, due to the emergence of Cyber-Physical Systems (CPS) and the Internet of Things (IoT), which employ sensor devices for communication. Although the sensor has resource constraints in computation, memory, bandwidth, and energy, a routing protocol is required to provide a safe and reliable path to ensure communication. This path is built by selecting appropriate nodes that are traversed from one end of the network to another. However, several security approaches used by routing protocols are inefficient in mitigating attacks. This is because of the high resource consumption of the pertinent mechanisms employed for the security solutions on the sensor node. Therefore, resource-bound security solutions are highly needed to provide minimal active security protection. Resource-bound security solutions are the process of using improved protocol's operation semantics to provide adequate security. It can be activated when needed to optimize protocol performance while minimizing security threats using minimal resource consumption. In this situation,it is important to take into account attackers that are able to temporally determine the presence of data in nodes and, importantly, to predict the next forwarding node. Attackers successful in such a siege can further decide to drop all, partially drop, or insert data into the packet. Any of the attacks can drastically degrade the performance of a network to an undesirable level. Routing Algorithm for Wireless Sensor Networks  
Other important challenges are to identify appropriate forwarding nodes that would mitigate packet loss, a higher performance in packet delivery, as well as provide a better trade-off between security and performance. In Reference [2], a Fuzzy-based Geographic Forwarding protocol (FuGeF) is proposed to improve node selection. The protocol first utilizes a pseudo-random form of dynamism and relies on parameters such as remaining energy, connectivity cost, and progressive distance for node selection. It then employs a Fuzzy Logic System (FLS) for decision-making. The goal of FuGeF is to identify appropriate forwarding nodes that would mitigate packet loss as well as provide a better trade-off between security and base performance. Extensive simulation experiments have been conducted to evaluate the performance of the proposed FuGeF with the Dynamic Window Secured Implicit Geographic Forwarding (DWSIGF) protocol. The results obtained in Reference [2] show that the FuGeF achieves a higher performance in terms of packet delivery ratio and minimizes the possibility of choosing an attacker as compared to the DWSIGF protocol. In Reference [2], the proposed approach builds on the DWSIGF protocol, leveraging the use of the three abovementioned parameters, as well as an FLS for node selection. These parameters describe features external to a node, as well as influence the distribution of the traffic load among the nodes. The FLS is used to evaluate the chance value of each next hop node based on its three criteria values. The values obtained are used to determine the most appropriate forwarding node for the routing process. Additionally, the dynamism introduced in DWSIGF was maintained with a slight modification such that a shift in the proposed protocol semantics is also achieved. The main aim of the proposed FuGeF is to achieve efficient security while maintaining an acceptable level of base performance. In an effort to mitigate the effect of attacks on a network, a resource-bound security solution suggests altering the protocol semantics or installing mechanisms that would prevent the selection of a malicious entity as well as maintain the base performance of the protocol.