## 6 Prototype Implementation and Evaluation
### System Evaluation  
Although the experimentation was performed in a laboratory setting, the hardware equipment is deployable in a vehicle as is: Kerlink's Wirma Road (IPv6 Gateway) is a low-consumption PC platform dedicated to vehicles, whereas eHealth devices are used by professionals of health for periodic check-up and continuous monitoring. The IPv6 kernel support and its associated protocol extensions are implemented in the gateway (not off-the-shelf technology). In the joint testbed, the MR runs router advertisement daemon (radvd), version 1.8.5, compiled for ARM platforms and available for Debian distributions [34]. The radvd is configured to advertise at regular intervals or immediately on solicitations, two different prefixes for two different interfaces. On the air interface (AP), which is bridged to the MR, the 2001:DB8:B:2::/64 prefix is advertised for the devices, which connect to the \"EXALTED\" ESSID. This is the ingress interface of the MR. On the Ethernet side, the 2001:DB8:A:1::/64 prefix is announced for the connected devices. This is the egress interface of the MR. The server is connected on this side of the MR, and the traffic is routed through the gateway from one end to the other. These devices form the basis of what will be deployed in a vehicle,  
Figure 9: Vidavo eHealth devices. such as an ambulance. Figure 10 shows a snapshot of the eHealth sub-testbed of our platform and Figure 11 shows the detail of the network configuration obtained on the cluster head once connected to the mobile router. In an effort to evaluate the throughput expected on the 3G uplink (infrastructure access) of the mobile router, we performed a comparison using two different services on the cellular interface. The graphic in  
Figure 11: Android Cluster Head connected to the MR. The Request for Comments (RFC) 4941 privacy extension IPv6 addresses are used to issue connections towards the personal health record (PHR). This is a privacy-related precaution completed by the use of a secure SSL connection on the application layer. Figure 10: eHealth testbed snapshot. On the left, the Android cluster head of our setting running the Vida24 eHealth application that collects measurements from the oximeter device (on the right). Multiple devices can be paired and monitored, for example, the Spirometer device on the top of the figure. Figure 12 shows the throughput for the 3G high speed uplink packet access (HSUPA, LTE-Release 6) infrastructure link in two conditions: enterprise public IPv4 access point name (APN) connection and an experimental IPv6 APN. Of course, IP version does not determine the obtained throughput, but the quality of the cellular deployment does (in particular, the provision for adequate quality of service). Figure 12A shows a throughput measure performed using a public Enterprise IPv4 APN. From the server perspective, the throughput is measured for a total amount of 15.6 Mb data received over a period of 64.1 s, which sets the overall throughput to 2.04 Mbits/sec (that is an average of 0.255 Mb/s). Figure 12B shows the throughput measured over an experimental IPv6 APN specially deployed for our V2I experiments. From the server perspective, a total amount of 17.4 Mb data over 60.6 s is received, which sets the overall throughput to 2.40 Mbits/sec (that is, an average of 0.3 Mb/s). This highlights the delay and throughput performance of the experimental IPv6 APN (not public), which are equivalent to those of a public IPv4 APN regarding these criteria. This also demonstrates the feasibility of IPv6 end-to-end communications over the already deployed technologies (3G+). The server, which is located on the Internet side (Egress interface), configures an IPv6 addresses on the 2001:DB8:A:1::/64 prefix. The server is then ready to receive the data. The server application runs over Java (tomcat webserver) and includes a MySQL database, where the collected data is stored and organized per user ID.