GeoSAC is a mechanism that enables IPv6 address autoconﬁgur ation in vehicular networks based on geographic routing. It is built using one of the most know networking stack in the ﬁeld of VANET, the one proposed by the car-to-car conso rtium. GeoSAC adapts the existing IPv6 stateless address autoconﬁguration prot ocol to VANETs. In this thesis we analytically model GeoSAC in order to evaluate its perfomance, especially in terms of conﬁguration times. Then we propose an optimization for this protocol using router advertisement caching which has also been modeled. We validate both the model we proposed by means of simulation. Simulation results show that our optimization signiﬁcantly improves the performance in terms of conﬁguration time but also for si gnalling overhead.