# Cluster-Based Routing Protocol with Static Hub (CRPSH) for WSN-Assisted IoT Networks
## 2 Literature Review
They must communicate with the hub through nonhotspot ARNs. This intern places an additional burden on nonhotspot ARNs. As a result, the energy consumption of nonhotspot ARNs is rather high, therefore increasing the overall energy consumption of the network [45]. [PERSON] and [PERSON] proposed VGBST consists of a group of cells that are responsible for rebuilding new routes depending on the present location information of the IoT hub [46]. A virtual infrastructure is designed by dividing the entire field into grids of equal-sized cells. The selection of cell headers in the network depends on the IoT devices, which are very close to the cell's center, which monitors the mobile IoT hub's position. The rest of the IoT devices other than CHs send data to the closest CH, and this CH forwards to the CH adjacent to it by using gateway IoT devices. Grid-Based Reliable Routing (GBRR) was proposed by [PERSON] et al., where communication quality helps choose the succeeding communication hop [47]. It is performed by creating virtual square grids of equal size such that each grid contains a few IoT devices. Total energy consumption is minimized with the help of the present position of IoT devices and grids, which is helpful for clustering. A cluster can occupy one or more grids, and the elected CH is responsible for managing the intracluster and intercluster communication. The routing algorithm helps to construct the productive paths inside a cluster and between the clusters to avoid overloading. All IoT devices are not used in the path while transferring the data from the source IoT device to the base station. A Mode-Switched Grid-Based Sustainable Routing Protocol (MSGR) for Wireless Sensor Networks is an energy-efficient routing protocol which partitions the entire sensing region into virtual grids of equal size [48]. In this scheme, each grid IoT device is selected as a grid head, and the path to the IoT hub is constructed using the grid head. This scheme improves network lifetime by switching the grid heads between active and sleep modes such that every grid head does not take part in establishing a path to the IoT hub at the same time. A path is built to the IoT hub by the active grid heads. Data is sent directly to the IoT hub by active grid heads in the IoT hub path. From the grid head's coordinate, we can infer whether it is in active or sleep mode. Table 1 illustrates the comparison among the existing protocols by considering several factors. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Protocol** & **Classification** & **Mobility** & **Energy** & **Scalability** & **Delay** \\ \hline CCS [49] & Chain Based & No & Very Low & Low & Large \\ \hline EBCRP [50] & Chain Based & No & Very Low & Low & Large \\ \hline PEGASIS [51] & Chain Based & No & Very Low & Very Low & Very Large \\ \hline CHIRON [52] & Chain Based & No & Moderate & Low & Small \\ \hline BATR [53] & Tree Based & No & Low & Low & Large \\ \hline EADAT [54] & Tree Based & No & Moderate & Low & Large \\ \hline PEDAP [55] & Tree Based & Yes & Moderate & Low & Moderate \\ \hline ETR [56] & Tree Based & No & Moderate & Moderate & Moderate \\ \hline TTDD [57] & Grid Based & Yes & Very Low & Moderate & Very Large \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Comparison of Routing Protocols for WSN-assisted IoT Networks.