## 4 Simulation Results  
The performance of the proposed routing has been evaluated by simulations done in a MATLAB modeling environment. A topology of 200 sensor nodes deployed randomly on an area of 600 \(\times\) 600 m\({}^{2}\) is used for simulations. A single sink moves randomly in the area of deployment with constant speed. Experiments model 60 min from simulation time. Each case is simulated 20 times with different seeds in order to eliminate the effect of the stochastic nature of some simulation events. On the other hand,the lifespan of each node is equal to the end of the battery life of each node. Wide ranges of different scenario with varying network sizes and sink speed values are defined and used. The default parameters used in our simulations are presented in Table 1.  
Performance Ring Routing has been compared with gravitational search random optimization algorithm with a ring, line-based data dissemination and Railroad based on determined performance measures:  
1- Average energy consumption per any node;  
2- Average report delay. Figure 12 shows the average energy consumptions of proposed method, Ring Routing (method 1), line-based data dissemination (method 2) and Railroad (method 3) for varied sink speed values. The average energy consumption of proposed routing is lower than three other states, and this will make the performance of this method better. Line-based data dissemination for lower speeds has better performance than Railroad, however, it has a reverse relation by increasing the speed. Line-based data dissemination uses the broadcast method for disseminating data search along with line structure, and an increased sink speed results in an increased number of dissemination followed by increased energy consumption. On the other hand, in the Railroad, instead of the dissemination method, searching is shared by unique forms along with the rail until a station has been created. Thus, Railroad performs better than line-based data dissemination for quicker sink speeds. Figure 13 shows the average reporting delays of proposed method, Ring Routing, line-based data dissemination and Railroad for different sink speeds. In most cases, line-based data dissemination \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameter** & **Value** \\ \hline Area of Deployment Number of Nodes & 600 \(\times\) 600 m\({}^{2}\) \\  & 200 \\ Communication Range & 80 m \\ Data Packet Size & 40 bytes \\ Reporting Frequency & 1/60 s/node \\ Buffer Size & 20 packets \\ Battery Capacity & 5000 Mj \\ Sink Speed & 0; 3; 6; 9; 12; 15 km/h \\ Number of Repetitions & 20 \\ Modeled Simulation Time & 60 min \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Simulation parameters. Figure 12: Comparative performance: average energy consumption for variable speeds of a sink. performs to some extent better than proposed routing, and Ring Routing has also a performance close to proposed routing; while Railroad has the worst performance for all above cases. In the proposed routing, Ring Routing and Railroad, the request/answer mechanism for spatial data of anchor node has been used, while in line-based data dissemination, a direct in-line data dissemination was used to remove the cost of a delay for answering the request of spatial data of the anchor node. However, this provides the condition for linear nodes to process large amounts of data causing high energy consumption in line-based data dissemination. Grid density and total traffic loads depend on the grid size, thus, besides the speed parameter, which is an effective parameter on performance of wireless sensor network, the number of sensor nodes will also have considerable effect on network performance. Thus, performances of protocols were also simulated in different numbers of sensor nodes (100, 150, 200, 250, and 300) on a fixed area of 600 \(\times\) 600 m\({}^{2}\). Figure 14 shows that for all states, the average performance of energy consumption in the proposed method is better than Ring Routing, line-based data dissemination and Railroad.