• Underwater Acoustic sensor networks (UWSNs) are the next generation’s networks.
  • The unique characteristics of the aquatic environment, that is low propagation speed, limited bandwidth, absence of GPS signaling, floating node mobility and limited acoustic link capacity are different from those of RF based networks.
  • Moreover, the energy is also limited. Many kinds of research are going to overcome this problem and the network protocol design, especially in MAC and PHY layer, has already succeeded.