Non-IP Multi-protocol Stack for Vehicular Communications

Abstract

Wireless vehicular communications are gaining momentum, mainly to improve road safety through the use of cooperative systems. Such visionary cooperative applications are based on recently established families of standards, notably the IEEE Wireless Access for Vehicular Environment (WAVE) and the ETSI ITS G5. Despite some relevant differences, both family of standards share the same physical and MAC layers, described in the IEEE 802.11:2012 - amendment 6, also know as IEEE 802.11p. Due to the characteristics of the wireless communications in vehicular environment, e.g., high-speed mobility causing unpredictable time-varying changes in connectivity, IP protocols are not suitable for safety communications as they require channel scanning, authentication and association under strict time limits. Safety vehicular communications rely, instead on non-IP protocols, either the WAVE Short Message Protocol (WSMP) or the FAST Network and Transport Protocol (FNTP). In this paper, we explore some of the challenges of implementing such protocols, and designed an architecture for a stack capable of handling both standards. The proposed architecture, including the communication and transport layers of the stack, was implemented in a custom ETSI ITS G5 compliant platform (IT2S), and its performance was assessed using a prototype.