Impact of the Pre-Authentication Performance in Vehicular Networks

The possibility of connecting vehicles to fixed IP networks through roadside units (RSUs) or even access gateways is seen as a very interesting alternative to fully infrastructure-less VANETs. However, getting access to those fixed networks must be controlled and only authorized users should be able to use those RSUs or gateways. However, that authentication process incurs in a not-negligible delay which can result in packet losses and other issues during handoffs. In this paper we assess the performance benefit provided by pre-authentication schemes in which vehicles use the current gateway to authenticate with nearby gateways before they finally attach to them. Our simulation results show that pre- authentication offers important benefits in terms of packet delivery ratio and handoff delays both in urban and inter-urban scenarios.