The industry's recognized authority for design, engineering and application of equipment and services in the global ocean community
Issue link: http://sea-technology.epubxp.com/i/653412
30 st / March 2016 www.sea-technology.com The 188 sensors were randomly deployed in the 3D wa- ter simulations, with a volume of 1,000 by 1,000 by 500 m. In one type of scenario, all nodes were stationary. The simulations lasted for 3,600 s, and the results were obtained from an average of 10 runs with a confdence interval of 99 percent. We also evaluated simulation results in a type of scenario involving mobile underwater sensors. Each sensor node ran- domly selected a direction and moved with a random speed between 1 m/s and 3 m/s. Results We have analyzed routing protocols as traffc engineer- ing tools in terms of packet delivery ratio, energy effciency and average end-to-end delay for underwater surveillance systems. We considered two different node deployment strategies, random and octahedron placement, for analyzing QoS parameters in equal conditions. Our simulation results show that with an octahedron placement strategy, HH-VBF and VBF performed the best in terms of average end-to-end delay and energy effciency. When the sensor nodes were mobile, DBR and FDBR performed better in terms of eff- cient energy consumption and average end-to-end delay. ST Reza Mohammadi graduated with an M.S. in computer networks from Shiraz University of Technology in Iran in 2013 and is now a Ph.D. student. His re- search focuses on underwater wireless sensor networks and traffc engineering in communication networks. Dr. Reza Javidan graduated with an M.S. in computer engineering from Shiraz University of Technology in 1996. He received his Ph.D. in computer engineer- ing from Shiraz University in 2007. His research is in computer networks and sonar systems. Javidan is now an assistant professor at the Department of Com- puter Engineering and Information Technology at Shiraz University. Performance Evaluation In order to analyze the mentioned routing protocols' QoS parameters, we conducted several experiments to test their performance under different operating conditions. To perform these experiments, we used the Aqua-Sim, an NS2- based underwater simulator. For comparing routing protocols in equal conditions, we used 188 nodes in all scenarios. Nine source nodes were placed at the bottom layer. Nine surface buoys (surface sink) were deployed. The maximum transmission range was 200 m (spherical), same as the interference range. In all our simulations, we set the parameters similar to LinkQuest's UWM1000 underwater acoustic modem. The initial energy of each node was 10,000 J. We set the size of data packets to 200 bytes. The bit rate was 17.8 Kbps. The power con- sumption in receiving, sending and idling modes were 0.75 W, 2 W and 10 MW, respectively. "One of the major tools in underwater traffc engineering is routing."