Many studies demonstrated that Mobi

Many studies demonstrated that Mobile Ad hoc
networks routing protocols are not suitable for Vehicular ad
hoc networks; the main reason relies on high mobility that
causes a rapid topology change that leads to partitioning and
routing link failure issues. Adap
table existing schemes also
demonstrated a poor network pe
rformance, especially when
the network density increases. The alternative is to develop
new efficient routing schemes for VANETs. Trajectory based
routing where the packet is forwarded from the source to the
destination based only on vehicle’s trajectory information
constitutes one class of forwarding protocols that are proposed
for VANETs. This paper surveys such class of protocols, with a
particular interest on their main features that have made them
efficient for VANETs, and their comparison with respect to
some standards metrics. Future directions with respect to
VANETs routing schemes are also discussed.