In vehicular ad hoc networks (VANETs), the communication links are inherently unstable due to vehicles¡¯ mobility and
various impairment of radio signal. Existing geographic routing protocols often choose the next hop according to the
greedy forwarding, regardless of the link¡¯s quality and transmission reliability. The successful packet delivery rate is
decreased in non-ideal communication links. Consequently, the reliability of data transmission is worse and the
network throughput is declined. In this paper, we propose a routing protocol called link state aware geographic
routing protocol (LSGR) for VANETs. In LSGR, a routing metric called expected one-transmission advance (EOA) is
contrived to improve the greedy forwarding algorithm by explicitly incorporating the link state and packet¡¯s advance.
Routing with the EOA metric, one can improve the transmission efficiency by diminishing transmission failures.
Simulation results show that LSGR can achieve a higher throughput and packet delivery rate than the geographic
routing protocols that adopt the traditional greedy forwarding.