A vehicular network must ensure a trust relationship
among participating “smart vehicles” (vehicles installed with
wireless network devices) and roadside infrastructure in order to
maximize the benefit provided by the network. In this paper, we
present practical ways to provide reliable reputation scores for
vehicles in a vehicular network. Because in most of the time, the
majority of people drive their vehicles locally for their daily
commute (to work places, schools, daycares, superstores, etc),
most vehicles have their predefined constant daily trajectories.
Based on this phenomenon, roadside infrastructure could rely on
repeated daily observations of the same set of passing-by vehicles
to build long-term reputation scores for these local “community”
vehicles, in the similar way as the reputation built-up for people in
a club or a church community. The proposed scheme does not
require sufficient density of smart vehicles and only requires each
smart vehicle has one secret and verifiable certificate. These
features make it especially suitable for the initial deployment
stage of vehicular network when the penetration rate of smart
vehicles is very low and vehicle-based public-key infrastructure is
vehicular networking security, reputation system,
initial deployment stage, roadside unit
Vehicular Ad hoc Network (VANET) is a form of mobile
ad-hoc network to provide communications among nearby
vehicles and between vehicles and nearby roadside equipments
. Applications of VANET include emergency/safety
warning, driving directions, cooperative driving, information
exchange between nodes/vehicles, access to Internet, location
aware advertising, on demand content, file sharing, etc .
For the success of all these applications, it is critical to ensure
that VANET can provide reliable and secure data transmission,
and full cooperation from all or most vehicles.
Most previously proposed VANET architectures and
applications (including security architectures) have an implicit
assumption that there are sufficient number of vehicles
equipped with wireless devices (called “smart vehicles”) on
roads when a proposed architecture is deployed. Under this
assumption, in most of the time VANET can rely on
Vehicle-to-Vehicle (V2V) communication and multi-hop
communication to achieve its functions and service.
This assumption, however, is not a realistic assumption
during the long initial years of VANET deployment. Due to the
huge population of existing non-smart vehicles and the long
lifetime of vehicles, it will take years or even decades transition
period before we could have a mature VANET environment
where most vehicles are smart vehciles.
Thus instead of
focusing on mature VANET scenarios, it is more important to
develop economical and feasible architectures that are suitable
for VANET initial deployment stage.