# ICN-Oriented Mobility Support Method for Dynamic Allocation of Mobile Data Flows
## 5 Evaluation
### Results and Discussions
#### 5.3.1 Average Packet Delay  
Figure 4a shows a comparison between the average packet delay and mobile data flow rate of different mobility support methods in Scenario 1. We find that at the same mobile data flow rate, our proposal performs better in terms of average packet delay than MAP-ME and the OPT. When the mobile data flow rate is lower than 4 Mbit/s, the average packet delay for the OPT and DAFM is the same and lower than the average packet delay of MAP-ME, which can be attributed to both the OPT and DAFM taking the shortest path as the switching path. The OPT broadcasts special data packets through the new location  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Parameter** & **Value** \\ \hline Data flow rate (\(R\)) & [1,10] Mbit/s \\ Average packet size (\(P\)) & 1000 bytes \\ Number of data flows (N) & [1,10] \\ The maximum queue length (\(Q\)) & 100 packets \\ The maximum number of entries in the router’s MFT (\(N_{max}\)) & 10 \\ The initial space occupancy rate of the router’s MFT (\(w\)) & [0,1] \\ Time interval for consumer disconnection and reconnection & 100 ms \\ from P-AR to N-AR (\(T_{PN}\)) & [1,5,10] ms \\ Response latency between NRSs and ARs (\(T_{PN}\)) & 5 ms \\ Wired link delay (\(T_{l}\)) & 5 ms \\ \hline \hline \end{tabular}
\end{table}
Table 2: Experiment parameters and values.  
Figure 3: Simulation topology.  
access router (R4) to make the switching path converge to the shortest path (Producer->R1->R4->Consumer) calculated by the routing plane. The DAFM selects R1 as the late-binding node through the late-binding selection algorithm to form the shortest switching path. MAP-ME converges the switching path to Producer->R1->R2->R3->R4->Consumer by sending an Interest Update (IU) message to the old location before moving. However, when the mobile data flow rate is higher than 4 Mbit/s, the bandwidth of the shortest switching path used by the OPT cannot meet the requirements for data transmission, resulting in a large delay. When the mobile data flow rate is higher than 4 Mbit/s and not more than 8 Mbit/s, the average packet delay of the DAFM is lower than that of MAP-ME because the DAFM selects R2 as the late-binding node, and the delay in forming the switching path (Producer->R1->R2->R4->Consumer) is lower than that of MAP-ME. When the mobile data flow rate is higher than 8 Mbit/s, the average packet delay of the DAFM is the same as that of MAP-ME because the DAFM selects R3 as the late-binding node, thus forming the same switching path as MAP-ME.  
Figure 4b shows a comparison between the average packet delay and the number of mobile data flows for different mobility support methods in Scenario 2. We can observe that with the same number of mobile data flows, our proposal performs better in terms of average packet delay than MAP-ME and the OPT. Both the OPT and MAP-ME adopt fixed switching paths to transmit data. When the number of mobile data flows exceeds four, the bandwidth of the switching path used by the OPT cannot meet the requirements of data transmission, resulting in a significant increase in average packet delay. The bandwidth of the switching path adopted by MAP-ME can meet the requirements for transmission of data flows, so the average packet delay does not change with an increase in the number of mobile data flows. The DAFM allocates multiple data flows to different routers so that the data flows can be transmitted on different switching paths. Therefore, we observe that the average packet delay of the DAFM is lower than the average packet delay of MAP-ME.  
Generally, the DAFM dynamically selects the switching path for mobile data flows. Compared with the fixed-path mobility support methods, our proposal can reduce the average packet delay to a certain extent.