# Cluster-Based Routing Protocol with Static Hub (CRPSH) for WSN-Assisted IoT Networks
## 4 Proposed Protocol
### Cluster Head Selection and Cluster Formation
This approach extends the network's life. If a device has less residual energy than the threshold, it does not participate in routing or becoming a CH but instead functions as a cluster member. ## 5 Simulation Results

The complete set of simulations is carried out using Castalia simulator. Table 2 shows the parameters used for simulation. ### Average Energy Consumption

The average energy consumption for each protocol is depicted in Figure 1. It is observed that the proposed protocol (CRPSH) has a lower control packet overhead than PCMRP and REDCL. The proposed scheme does not employ flooding and does not involve the entire network in selecting CHs and multipaths. The hub selects the CHs and routing paths on its own. PCMRP, on the other hand, creates a multipath by flooding control packets across the network. This is a significant contributor to the increase in control packet overhead. Additionally, the multipath is reconstructed if any device becomes the source. This adds to the protocol's overhead. PCMRP transmits data via the shortest path possible. However, because of the increased overhead associated with control packets, the average energy consumption is higher. \begin{table}
\begin{tabular}{l l} \hline \hline
**Parameter Name** & **Value** \\ \hline Network Size & \(100\times 100\) m\({}^{2}\) \\ Number of sensor devices & 100 \\ Data packet size & 512 bytes \\ Control packet size & 32 bytes \\ Initial energy & 1 J \\ \(E_{Emlb}\) & 50 nJ/bit \\ \(E_{f\text{s}}\) & 10 pJ/bit/m\({}^{2}\) \\ \(E_{mp}\) & 0.0013 pJ/bit/m\({}^{4}\) \\ \(d_{0}\) & 87 m \\ \(E_{Comp}\) & 5.1/bit \\ \(E_{low}\) & 0.2 nJ/s \\ Simulation time & 400 s \\ MAC protocol & TMAC \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Simulation Parameters. The efficiency of the routing protocol relies on energy consumption. The smaller the network energy consumption, the greater the network lifetime. Therefore, it is the total energy consumed by IoT devices to perform transmission, reception, processing, and sleeping activities.The REDCL method prioritizes the selection of a smaller number of active reporting nodes (ARNs) in hotspot areas over the selection of more ARNs in non hotspot areas. The REDCL method converges the paths of several ARNs monitoring an event outside of non hotspot zones and sends them to the hub after data aggregation. The hotspot area's ARNs are unable to transfer data directly to the hub. They must communicate with the hub through non hotspot ARNs. This intern places an additional burden on non hotspot ARNs. As a result, the energy consumption of non hotspot ARNs is rather high, therefore increasing the overall energy consumption of the network. ### Average End-to-End Delay

It is calculated as the time it takes for a data packet to be generated at the source and received successfully at the sink. Each potential cluster head in the PPCMP must wait before becoming the cluster head. Furthermore, when the source node changes, the protocol must recreate the multipath for the new source node for each new event. This increases the protocol's total latency. The REDCL approach sends data packets to the principal route based on a single event. It collects data before sending it to the hub, which causes packet delivery to be delayed. CRPSH, on the other hand, allows for various pathways to be taken. The proposed protocol has a more reduced end-to-end latency than PCMRP and REDCL, as shown in Figure 2.

Conversely, for CRPSH, multiple paths are available. The result in Figure 2 indicates that the proposed protocol's end-to-end latency is less than that of PCMRP and REDCL. Figure 1: Average Energy Consumption. Figure 2: Average End-to-End Delay. ### Packet Delivery Ratio

It is defined as the ratio of IoT hub receipt data packets to data packets sent by the source. For each protocol, the packet delivery ratio is illustrated in the Figure 3. PCMRP employs node-disjoint multipath routing, that improves reliability and, as a result, the delivery ratio.