Vehicular networking requires high message transmission
rate but also faces limited radio resources. This may lead
to congestion in the radio access network and incur long delay for
the messages. On the other hand, applications also have stringent
requirement for latency (or freshness) of the received information.
In this paper, we focus on cellular-based vehicular networks
and propose a method for finding an optimal trade-off between
network congestion and the freshness of received information. We
suggest a feedback-based scheme for vehicles and a centralized
entity (GeoServer) to coordinate with each other to determine
a message transmission rate that best satisfies the application
requirements. We first outline the framework of the proposed
mechanism, and then analytically derive the optimal solution.
Following that, the performance of the proposed mechanism is
evaluated via simulations.