  Underwater wireless sensor networks (UWSN), similar to the terrestrial sensor
networks, have different challenges such as limited bandwidth, low battery
power, defective underwater channels, and high variable propagation delay. A
crucial problem in UWSN is finding an efficient route between a source and a
destination. Consequently, great efforts have been made for designing efficient
protocols while considering the unique characteristics of underwater
communication. Several routing protocols are proposed for this issue and can be
classified into geographic and non-geographic routing protocols. In this paper
we focus on the geographic routing protocols. We introduce a review and
comparison of different algorithms proposed recently in the literature. We also
presented a novel taxonomy of these routing in which the protocols are
classified into three categories (greedy, restricted directional flooding and
hierarchical) according to their forwarding strategies.
