# An Efficient Probe-Based Routing for Content-Centric Networking
## 4 Performance Evaluation
### Experimental Results
#### 4.4.5 Analysis of QoS  
QoS is described as the network's use of various technologies to provide better service capabilities for specific network communications in the field of computer networking and other packet-switched telecommunication networks [43]. It is also a measurement of a network's overall performance. Especially for streaming multimedia scenes, it is very important, such as video conferences. The service capability of network communication facilities to meet end-user needs can be evaluated qualitatively and quantitatively using QoS [15; 43]. For QoS analysis, the four performance metrics in Section 4.3, _throughput_, _packet loss_, _delay_, and _jitter_, are used. The QoS category is based on the literature [15]. According to the experimental results, both basic CCN and our approach are in the same QoS category. In terms of real values, however, our approach outperforms others.  
Table 3 demonstrates QoS results. For throughput, both the basic CCN and our approach belong to the \"Good\" QoS category, because according to the literature [15], the throughput of \"good\" category is greater than 75 packets per second. _PIT probe_ and _FIB probe_ transmit two and six packets per second more than the basic CCN, respectively. This shows that our approach is better than basic CCN in improving network congestion.  
Packet loss of the basic CCN and our approach also belong to the \"Good\" QoS category because their results are less than 15% [15]. Furthermore, packet loss of _PIT probe_ and _FIB probe_ is reduced by 0.86% and 1.06%, respectively, compared to the basic CCN. For throughput and packet loss, _FIB probe_ performs slightly better than the basic CCN and  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**QoS Parameter**} & \multicolumn{2}{c}{**Methods**} & \multirow{2}{*}{**QoS Category**} \\  & **Basic CCN** & & **PIT probe** & _FIB probe_ \\ \hline Throughput packets/s & 85 & 87 & 90 & Good \\ Packet loss/\% & 11.4 & 10.54 & 10.34 & Good \\ Delay/ms & 275 & 217 & 221 & Bad \\ Jitter/ms & 183 & 116 & 126 & Bad \\ \hline \hline \end{tabular}
\end{table}
Table 3: QoS parameters in three approaches.  
PIT probe. FIB probe_ improves the accuracy of the routing table and alleviates network congestion by finding the best content provider and the shortest path to the nearest content.  
For delay and jitter, both the basic CCN and _PIT probe_ are greater than 125 ms. According to the literature [15], they belong to the \"Bad\" QoS category. _PIT probe_ performs similarly to the other two methods in terms of delay. However, it has a jitter of 116 ms, which is less than 125 ms. Thus, it belongs to the \"Good\" QoS category. This shows that the network delay variation of _PIT probe_ is more stable than the basic CCN and _FIB probe_. _PIT probe_ is superior to the basic CCN and _FIB probe_ in terms of delay and jitter. This is consistent with the results shown in Figures 6 and 7. _PIT probe_ directly reduces customers' waiting time by selecting the most popular PIT entry as a probe to find the best content provider. Hence, _PIT probe_ gets superior performance on response time than other approaches.  
Although basic CCN and our approach are in the same QoS category. However, our approach performs better in terms of real values.