IP communications in the car : an ecosystem enabler
Résumé
The recent boom in wireless networks technologies and the diversification of the network-enabled devices opened the way to a lot of network-based services. In a very near future, users will expect to be permanently connected to the Internet no matter where they are, and especially in cars and public transportation. Nevertheless, current technologies does not allow these small-sized devices to have more than one or two wireless interfaces due to energy consumption, size and cost issues. Therefore, these devices would not benefit from the diversity offered by the availability of various wireless access technologies. Moreover these type of tiny devices are not supposed to be able to manage their own mobility and to maintain an ubiquitous access to the Internet. However, considering the problem otherwise, one can notice that these devices are often used in environments such as personal vehicles and public transportation systems. Those environments can manage the ubiquitous access issues on behalf of the devices and provide them with a stable and easy-to-use access network (e.g. Wi-Fi or Bluetooth). To provide ubiquitous access to the Internet into vehicles, several aspects have to be studied in order to handle a seamless mobility through multiple access networks. A first step was the design of the NEMO (NEtwork MObility) Basic Support protocol by the IETF. The NEMO approach introduces the notion of Mobile Routers (MR) which will be part of modern vehicles and manage all complexities related to multi-interfaces and seamless mobility management. Real experiments conducted over wireless networks currently in commercial operation (e.g. GPRS, UMTS, CDMA2000, WiMax, WiFi) indicate that this kind of link suffer from several problems such as high and variable round trip times, burst of packet losses, frequent link outages, and significantly lower bandwidth than originally claimed. In other words, it seams that there is currently no wireless technology able to offer an adequate level of seamless connectivity without non affordable deployment and operational costs. In this context the most viable solution is to exploit what one call the network diversity. A node considers all reachable wireless networks as a mean to be connected to the Internet. In this heterogeneous world, it becomes possible to use simultaneously a combination of several networks, each of them being optimized for some particular service or for a particular geographical situation. This results in a system that should dynamically deliver each service via the network that is most efficient for that service in the current situation. The complexity of such a decision could not be afforded by tiny devices, therefore they have to collaborate with the decision point in the network on-board. It is then necessary to standardize a protocol between embarked equipments and mobile routers to allow the development of an ecosystem. In this talk, we first give a short introduction explaining why IPv6 is doubtless the only way to benefit from the Internet flexibility to ease the development of various services (from security to infotainment). Then we describe how the IP networking fit in the CALM architecture designed at ISO TC 204 WG 16. The main part of the talk deals with the network diversity (multihoming) management and gives an overview of the works done at standardization bodies and in the academic world. Will finish the chapter giving some insights into two French collaborative projects: the REMORA project which has designed a networking architecture and proposes solutions for some functionality that are missing in the IETF standards, the LoCoSS project provides emergency services with a prototype of an IPv6 Mobile Router to experiment the use of public networks for experimental enhanced services.