Geographic and Opportunistic Routing for Underwater Sensor Networks

Geographic and Opportunistic Routing for Underwater Sensor Networks

Geographic and Opportunistic Routing for Underwater Sensor Networks

Geographic and Opportunistic Routing for Underwater Sensor Networks


Underwater wireless sensor networks (UWSNs) have been showed as a promising technology to monitor and explore the oceans in lieu of traditional undersea wireline instruments. Nevertheless, the data gathering of UWSNs is still severely limited because of the acoustic channel communication characteristics. One way to improve the data collection in UWSNs is through the design of routing protocols considering the unique characteristics of the underwater acoustic communication and the highly dynamic network topology. In this paper, we propose the GEDAR routing protocol for UWSNs. GEDAR is an anycast, geographic and opportunistic routing protocol that routes data packets from sensor nodes to multiple sonobuoys (sinks) at the sea’s surface. When the node is in a communication void region, GEDAR switches to the recovery mode procedure which is based on topology control through the depth adjustment of the void nodes, instead of the traditional approaches using control messages to discover and maintain routing paths along void regions. Simulation results show that GEDAR significantly improves the network performance when compared with the baseline solutions, even in hard and difficult mobile scenarios of very sparse and very dense networks and for high network traffic loads.

PROJECT OUTPUT VIDEO: (Click the below link to see the project output video):


  • Depth-based routing (DBR) routing protocol is the first underwater sensor network routing protocol that uses node depth information to route data packets. The basic idea of DBR is to forward data packets greedily towards the water surface. Thus, packets can reach multiple data sinks deployed at the water surface. During the forwarding, the current sender broadcasts the packet. After receiving it, if the receiver is closer to the water surface, it becomes qualified as a candidate to forward the packet. Otherwise, it will discard the packet.
  • Each qualified candidate will forward the packet in a prioritized manner if its distance to the current forwarder is at least dth and it has not previously sent this packet previously. Node priority is given by means of the holding time. The farther the candidate node is on the current forwarder, the lower is its holding time.
  • After the holding time, the packet is broadcast if the node has not received the same data from a neighbor.


  • This can be expensive in terms of energy since the high energy cost of underwater acoustic communication and the impairments of the acoustic channel.
  • Moreover, as packets will be routed through more hops to circumvent the communication void region, the acoustic channel can be overloaded, increasing the average end-to-end delay and reducing the packet delivery ratio due to more collisions and retransmissions.


  • GEDAR is an anycast, geographic and opportunistic protocol that tries to deliver a packet from a source node to some sonobuoys. During the course, GEDAR uses the greedyforwarding strategy to advance the packet, at each hop, towards the surface sonobuoys.
  • A recovery mode procedure based on the depth adjustment of the void node is used to route data packet when it get stuck at a void node. The proposed routing protocol employs the greedy for-warding strategy by means of the position information of the current forwarder node, its neighbors, and the known sonobuoys, to determine the qualified neighbors to continue forwarding the packet towards some sonobuoys.
  • Despite greedy forwarding strategy being a well known and used next-hop forwarder selection strategy, GEDAR considers the anycast nature of underwater routing when multiple surface sonobuoys are used as sink nodes.


  • The works proposed a node’s depth adjustment to improve data packet delivery in static underwater sensor networks.
  • Differently, our node’s depth adjustment algorithm is devoted to the communication void region routing problem in mobile underwater sensor networks, acting in a reactive way to overcome changes in the network topology.
  • Moreover, we implement an opportunistic routing mechanism to mitigate the impairments of the underwater acoustic communication.






  • System : Pentium Dual Core.
  • Hard Disk : 120 GB.
  • Monitor : 15’’ LED
  • Input Devices : Keyboard, Mouse
  • Ram :



  • Operating system : Windows XP/UBUNTU.
  • Implementation : NS2
  • NS2 Version : 2.28
  • Front End : OTCL (Object Oriented Tool Command  Language)
  • Tool : Cygwin (To simulate in Windows OS)


Rodolfo W. L. Coutinho, Azzedine Boukerche, Luiz F. M. Vieira, and Antonio A. F. Loureiro, “Geographic and Opportunistic Routing for Underwater Sensor Networks”, IEEE TRANSACTIONS ON COMPUTERS, VOL. 65, NO. 2, FEBRUARY 2016.