Peng Xie, Zhong Zhou, Zheng Peng, Hai Yan, Tiansi Hu, Jun-Hong Cui, Zhijie Shi, Yunsi Fei, Shengli Zhou Underwater Sensor Network Lab 1
Outline Motivations System Overview Aqua-Sim Components Experimental Results Conclusions 2
Motivations Increasing interests in underwater networks High costs in doing large scale field tests Hard to evaluate the performance Lack of simulation tools Channel model Long propagation delay Three dimensional topology Next: Platform 3
Development Platform NS-2 simulator A discrete event simulator Widely used Open source Build in C++ Limitations 2D topology Designed for wired networks Does not support underwater networks Next: Overview 4
Aqua-SimOverview CMU wireless extension Support wireless mobile networks Not applicable to underwater networks Still for 2D network Aqua-Sim underwater extension In parallel with CMU wireless extension Designed for underwater networks Support 3D topology Implementation Object-oriented Dual interfaces C++ : Developers Otcl : Users Next: Classes 5
Class Structure Basic classes Entities underwaternode RMAC, etc. Interfaces underwatermac Functions hash-table, etc. Next: Phy Model 6
Physical Layer Model Channel Network entity Class: UnderwaterChannel Attenuation model Distance Frequency Transmission range Power Range Propagation Class UnderwaterPropagation Introducing delays Collision Packets copied to IncomingChannel Maintained by each node Collision decided by UnderwaterPhy Receiving time Receiving power level Can be extended to use any complex model Next: MAC 7
Media Access Control (MAC) Abstract interface class: UnderwaterMac Available protocols: Broadcast MAC Aloha T u -MAC R-MAC Next: Network 8
Network Layer Implementation Following NS-2 standard Customization Providing various interfaces Configuration Using Tclscript Available protocols: Vector-Based Forwarding (VBF) Depth-Based Routing (DBR) QELAR Next: Fidelity Case 9
Case Study: Fidelity Testing Experiment settings Sending speed: 80 bps Topology: 6 nodes in a one hop network Frame length: 32 bytes Traffic pattern: Exponential distribution Next: Fidelity Results 10
Case Study: Fidelity Testing (cont.) Throughput with increasing overall traffic Network load: 0.02 pkt/node/sec Throughput with fixed overall traffic Network Load: 0.1 pkt/sec Next: MAC Case 11
Case Study: MAC protocols Experiment settings MAC protocols: R-MAC T u -MAC Broadcast MAC Packet length 64 bytes Data rate 10 kbps Traffic: 0.01~0.05 pkt/sec Next: MAC Results 12
Case Study: MAC Protocols (cont.) Metrics Average throughput Average energy consumption per packet Average packet delay Next: Routing Case 13
Conclusions Aqua-Sim An extension of NS-2 simulator Specifically designed for underwater networks Support large scale networks Available at http://ubinet.engr.uconn.edu/mediawiki/index.php/aqua-sim http://uwsn.engr.uconn.edu/aquasim.tar.gz Future work 3D Animator Advanced channel models More protocols 14
Aqua-3D Pictures 15
Aqua-3D Video, University of Connecticut 16
Thanks! Questions & Comments? 17