# ICN-Oriented Mobility Support Method for Dynamic Allocation of Mobile Data Flows
## 5 Evaluation
### Simulation Setup  
The experimental platform was built on an Ubuntu 20.04 system. The experimental platform included Mininet 2.3.0, OpenvSwitch (OvS) 2.13.3, and Ryu [37] 4.34 controllers. This section describes how Mininet 2.3.0 was used to create a network topology. This paper simulates a multi-path network topology. The network topology and link bandwidth settings are shown in Figure 3. We used OvS 2.13.3 to simulate routers and realize data forwarding. Ryu 4.34 is a controller that can connect to OvS through the OpenFlow 1.3 protocol. In order to simulate mobility in Mininet, we modified its code to allow mobile nodes to switch from one router to another. In order to implement the proposed mobility support method, the mobile node needs to send a Mobile Event Message to the previous router before the mobile node disconnects from it. In order to simulate the connection of the mobile node to the new access router, a new link is created between the mobile node and the new access router. After reconnection, the new access router assigns a new network address to the mobile node. In our proposal, the latest binding relationship (EID-NA) of the mobile node is updated to the NRS. In addition, Mininet does not support layer 3 routing. In order to realize routing in a multi-path network topology, we ran a routing protocol on the controller. The routing algorithm adopted by the routing protocol was the Dijkstra algorithm, with bandwidth as the weight.  
We consider that the rate of the producer sending data flows is \(R\), the average packet size is \(P\), and the number of data flows is \(N\). The maximum queue length of the router is \(Q\), and the maximum number of entries in the router's MFT is \(N_{max}\), with the initial space occupancy rate of the router's MFT represented by \(w\). The time from the consumer leaving the previous access router (P_AR) to attaching to the new access router (N_AR) is \(T_{PN}\), the latency of the Name Resolution Systems (NRSs) responding to the access router's query is \(T_{RA}\), and wired link delay is \(T_{I}\). The delay of all wired links in the simulation network topology is the same. Table 2 shows the basic parameters and their values in our simulation. During the simulation, the producer continued to send data flows to consumers. The rate and number of data flows can be adjusted according to different simulations. One second after the simulation starts, consumer movement is simulated. The total simulation time is 3 s. For each round of simulation, we calculate the average value of the measured performance metrics.  
In order to evaluate the performance of the mobility support method in terms of average packet delay and packet loss rate, we simulated two scenarios.  
Scenario 1 is a scenario where a consumer requests a single form of content published by a producer. We fixed the number of data flows sent by the producer to 1, set the initial space occupancy rate of the MFTs of routers R1, R2, and R3 to 0.5, set the latency of the NRS responding to R3's query to 1 ms, and adjusted the speed of data flows from 1 Mbit/s to 10 Mbit/s. Scenario 2 is a scenario where a consumer requests multiple forms of content published by a producer. We set the rate of each data flow sent by the producer to 1 Mbit/s, set the initial space occupancy rate of the MFTs of routers R1, R2, and R3 to 0.5, set the latency of the NRS responding to R3's query to 1 ms, and adjusted the number of data flows from 1 to 10. Other parameters settings are shown in Table 2. In order to evaluate the performance of the mobility approach in terms of handover delay, we set the delay parameters of the NRS responding to R3's query as 1 ms, 5 ms, and 10 ms on the basis of simulation for Scenario 1.