  Data delivery relying on the carry-and-forward strategy of vehicle-to-vehicle
(V2V) communications is of significant importance, however highly challenging
due to frequent connection disruption. Fortunately, incorporating
vehicle-to-infrastructure (V2I) communications, motivated by its availability
in bridging long-range vehicular connectivity, dramatically improves delivery
opportunity. Nevertheless, the cooperation of V2V and V2I communications, known
as vehicular-to-everything (V2X) communications, necessitates a specific design
of multihop routing for enhancing data delivery performance. To address this
issue, this paper provides a mathematical framework to investigate the data
delivery performance in V2X networks in terms of both delivery latency and data
rate. With theoretical analysis, we formulate a global and a distributed
optimization problem to maximize the weighted sum of delivery latency and data
rate. The optimization problems are then solved by convex optimization theory
and based on the solutions, we propose a global and a distributed multihop
routing algorithm to select the optimal route for maximizing the weighted sum.
The rigorousness of the proposed algorithms is validated by extensive
simulation under a wide range of system parameters and simulation results shed
insight on the design of multihop routing algorithm in V2X networks for
minimizing latency and maximizing data rate.
