# Satellite Network Task Deployment Method Based on SDN and ICN
## 5 The Simulation Result
### Analysis of Task Deployment Method Based on Genetic Algorithm
In addition, we tested the impact of task computation on the utility function, so this experiment added three groups of experiments that kept the data required by the task unchanged. The computation of each task was \(2\times 10^{4}\), \(4\times 10^{4}\), and \(6\times 10^{4}\) MI, respectively. MI here represents the number of machine language execution instructions. From the experiment, it can be seen that after increasing the computation of the task, the value of the utility function increased significantly. The reason for this is that the increase in the number of calculations will deploy the task on the resource available node farther away from the initiating node, which will increase the response delay. The increase in the number of calculations will increase the processing delay consumed by the calculations. Figure 9 shows a graph of intranetwork traffic as a function of task input data. In the simulation experiment, the computational amount of the task was set to be unchanged, whereas the amount of data required for task processing was changed. It can be seen that, by increasing the amount of task input data, the network traffic was also increased. The reason for this is that, in the ICN-based communication mode, the communication data are cached in the mission-originating node or in other satellites on the same orbital plane as the mission-originating node. Nevertheless, with further increasing of the task input data, the cache space of the node located closer to the task-initiating node can no longer accommodate the needs of task deployment. Therefore, the task needs to be deployed to the available node farther away, which significantly increases the forwarding times in the network. The utility function task placement proposed in this paper is compared with the strategy of QoE-driven content deployment and random task deployment, as well as sending the task back to the ground cloud computing center. As can be seen in Figure 9, the communication volume brought by the plan of transmitting the mission back to the ground cloud computing center increases linearly. This is because, in using this approach,  
Figure 8: The graph of the value of the utility function as a function of equilibrium parameters. the data required by the mission can be completely transmitted back to the ground through fixed satellite hops before the calculations can be carried out. The utility function task deployment proposed in this paper has good performance in reducing the traffic caused by the task deployment. In Figure 10, we continued to investigate the influence of the cache space size of satellite nodes on the intranetwork traffic. In the simulation experiment, the average cache space of the satellite node was set to be within the range of 0-200 MB. It can be seen from the experiment that there is a small gap between the traffic in the network and the input amount of small tasks. The reason for this is that the cache node can be accommodated when the amount of task data are small. However, as the amount of task data increases continuously, the network with larger average cache space can perform better. Figure 11 shows the comparison of task processing response delays of different relative sizes under different content placement strategies. As can be seen from the figure, the utility  
Figure 10: The diagram of the effect of on-board cache capacity on network traffic. Figure 9: The comparison of network traffic with the amount of task input data. function task placement proposed in this paper can still guarantee a low response delay when the task size keeps getting larger. When the task size is low, the low delay response can be achieved by using the LEO satellite network. When the task scale is relatively low, the data required by the task are transmitted back to the ground computing center and the calculation results are transmitted back to the terminal through the satellite network as the main part of the delay.