# A Delay-Aware and Reliable Data Aggregation for Cyber-Physical Sensing
## 5 Performance Evaluation
### Evaluation on the Proposed Scheme with Different Parameters
Also, we could see that the advantage on network delay is more obvious with the increasing number of nodes scattered on the half sphere. When the randomly selected \(p=0.8\), the comparisons of the number of packet lost and network delay under different \(\mu\) are shown in Table 10. Figure 16 intuitively shows the results. As can be seen in Figure 16, the network delay is more obvious than the network delay. Figure 14: Comparison under different \(\mu\) for a network with 100 nodes when \(p=0.8\). (**a**) The network delay; (**b**) The number of packets lost. Figure 13: Comparison under different \(\mu\) for a network with 100 nodes when \(p=0.6\). (**a**) The network delay; (**b**) The number of packets lost. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Number of Packets Lost/Delayed \(p=0.6\)** & **TSR-DARDA** & **IWTSR** & **GVWTSR** \\ \hline \(\mu=0\) & 133.8000/24.0000 & 180.2000/69.0000 & 181.4000/87.0000 \\ \(\mu=1\) & 49.1000/30.9000 & 70.6000/96.9000 & 76.3000/117.3000 \\ \(\mu=2\) & 18.7000/36.9000 & 29.2000/109.8000 & 30.7000/136.5000 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Comparison of the number of packets lost and network delay under different \(\mu\) for a network with 500 nodes when \(p=0.6\). as well as delay into consideration. To address these problems, a novel routing scheme named TSR-DARDA is proposed. Carefully designed system parameters grant TSR-DARDA lower transport delay under given reliability constraints. The theoretical analysis shows that the method outperforms the existing methods in network delay. In addition, it can be seen from the simulation results that the network delay could be reduced while guaranteeing reliability. However, the characteristics of wireless communications are not considered fully, including the abundance of physical obstacles, multipath propagation and electromagnetic interference from equipment and coexisting wireless systems, etc. Besides, there are many interesting open questions to consider. Although we focus on the delay performance, other performance metrics such as time complexity and the communication overhead of the routing protocol are also of importance. It would be interesting to study the relationship between these metrics with data aggregation and network topologies. This work was supported in part by the National Natural Science Foundation of China (61272150, 61379110, 61472450, M1450004), Ministry Education Foundation of China (20130162110079 and MCM20121031), the National High Technology Research and Development Program of China (863 Program) (2012 AA010105) and the National Basic Research Program of China (973 Program) (2014 CB046305). [PERSON] conceived the method idea, designed and performed the experiments, analyzed the data, and wrote the paper. [PERSON] commented on the work. [PERSON] took part in the discussion, gave some suggestions, and assisted to modify the grammar mistakes in the paper. [PERSON] attended discussion on the problems of our research. The authors declare no conflict of interest.