# Cluster-Based Routing Protocol with Static Hub (CRPSH) for WSN-Assisted IoT Networks
## 2 Literature Review
The whole network region is partitioned into four equal planes by one horizontal and one vertical strip in the Rendezvous-Based Routing Protocol (RRRP). The rendezvous region is a horizontal and vertical strip of land. This virtual structure divides the network into four sections: 1--horizontal left, 2--horizontal right, 3--vertical up, and 4--vertical down. This intersection acts as a gathering spot. Devices that operate in this cross section are known as backbone devices. A tree was created in this area and some of the backbone devices are part of it. This tree is responsible for data transmission from the source to the hub and from the hub to the source [27]. The hub position is known by the devices that participate in tree creation, while the hub position is unknown to the other backbone devices. Space partitioning is accomplished using the quadtree structure of the network via the quadtree-based routing protocol (QDD). The following assumptions guide the development of this protocol: All stimuli and hubs are movable, but IoT devices are stationary and aware of their location. They are also familiar with their one-hop neighbors. The IoT devices are aware of the whole WSN-assisted IoT network, which is defined as 2 m \(\times\) 2 m, where m = log2. (N). For data and packet delivery, this protocol uses a greedy forwarding mechanism [28]. The building quadtree structure in QDD is modest as compared with other hierarchical techniques. The QDD has been unable to resolve the hotspot issue. For WSN-assisted IoT networks, the Centroid-Based Routing Protocol (CBRP) suggested an energy-efficient data routing protocol. It establishes the Candidate Cluster Head (CH) device, which ensures a consistent allocation of energy in the cluster. Cluster formation is delegated to the BS, which helps to reduce cluster formation overhead. The data packets are sent using a threshold distance. Data loss happens when the distance exceeds the threshold [29]. The procedure for re-electing cluster heads has yet to be established. The WSN-assisted IoT network is divided into sectors via the SCBC (Sector-Chain-Based Clustering Routing Protocol) (cluster). For each cluster, it creates a chain, with the chain leader functioning as the cluster head (CH) and secondary cluster head (SCH), both of which contain considerable residual energy. The SCHhas the smallest distance between candidate nodes and the network's base station (BS). The network's energy dissipation is decreased by using chains for data transfer. When compared with the CH, the SCH is used to save energy. The Base Station (BS) establishes clusters and selects a cluster leader, resulting in higher energy use in following rounds [30]. The LEACH protocol is available in a variety of variants that improve its performance. [PERSON] et al. propose LEACH-C, which uses a fixed number of CHs in subsequent rounds and assigns CHs to clusters via a base station [31]. Clusters are formed only once during the setup phase of LEACH-F and persist for the duration of the network [32]. New IoT devices are not permitted to join the network in this configuration. The network is controlled by BS, which transmits data via single-hop communication. [PERSON] et al. [33] propose a multihop LEACH, in which an optimal multihop tree is constructed between all CHs, with the IoT hub as the root. This path is responsible for communication in the network. Another version, MS-LEACH, uses one-hop and multihop communication for transmission, which depends on the cluster size proposed by [PERSON] et al. [34]. [PERSON] et al. propose an MR-LEACH that divides the entire network area into layers depending on the hop distances among the cluster heads [35]. The data is transmitted from the lower layer's CH to the nearest upper layer's CH until it reaches the IoT hub. The existing protocols [32; 33; 34; 35] increase the network lifetime but have a problem with hotspots in the network because of overtraffic near the base station.