Wednesday, 18th September 2013, 10:30 am (SCE Meeting Room)
Speaker: Professor Yunhao Liu (Dean of School Of Software,Tsinghua University, China)
Title: GreenOrbs and CitySee: Lessons Learned from Extremely Large Scale Sensor Network Deployment
"The world has just ten years to bring greenhouse gas emissions under control before the damage they cause becomes irreversible." This is a famous prediction raised by climate scientists and environmentalists recently. It reflects the increasing attention in the past decade from human beings on global climate change and environmental pollution. On the other hand, forest, which is regarded as the earth’s lung, is a critical component in global carbon cycle. It is able to absorb 10%~30% of CO2 from industrial emissions. Moreover, it has large capacity of water conservation, preventing water and soil loss, and hence reducing the chance of nature disasters like mud-rock flows and floods. Forestry applications usually require long-term, large-scale, continuous, and synchronized surveillance of huge measurement areas with diverse creatures and complex terrains. The state-of-arts forestry techniques, however, support only small-scale, discontinuous, asynchronous, and coarse-grained measurements, which at the same time incur large amount of cost with respect to human resource and equipment’s. WSNs have great potential in resolving the challenges in forestry. Under such circumstances, GreenOrbs is launched. The information GreenOrbs offers can be used as evidences, references, and scientific tools for human beings in the battle against global climate changes and environmental pollution. The prototype system is deployed in the campus woodland of Zhejiang Forestry University. The deployment area is around 40,000 square meters. The deployment started in May 2009 and included 50 nodes. In November 2009 it was expanded to include 330 nodes. The system scale reaches 400 in April 2010. The duty cycle of nodes is set at 8%. The network diameter is 12 hops. The sensor data are published online via the official GreenOrbs website. The Tianmu Mountain deployment includes 200 nodes and has been in continuous operation since August 2009. The deployment area is around 200,000 square meters. The duty cycle of nodes is set at 5%. The network diameter is 20+ hops. Till 2011, we totally deployed 2000+ sensor nodes for GreenOrbs project. In August 2011, we successfully deployed 1200 sensor nodes in an urban area in WuXi city, called CitySee. Now CitySee has been expanded into more than 10 cities in China. We plan to deploy 10,000+ sensor nodes for monitoring the environment comprehensively. We learned a lot of lessons during the deployment of GreenOrbs and CitySee. The experiment results in many publications, including ACM SenSys 2009, 2010, ACM Sigmetrics 2010, ACM SIGMOD 2011, IEEE INFOCOM 2010, 2011, 2012, 2013, ACM MobiCom 2012, and etc. In this discussion, we will focus on several open issues for extremely large scale deployment of sensor networks including routing, diagnosis, localization, link quality, and etc.
Yunhao Liu received his BS degree in Automation Department from Tsinghua University, China, in 1995, and an MA degree in Beijing Foreign Studies University, China, in 1997, and an MS and a Ph.D. degree in Computer Science and Engineering at Michigan State University in 2003 and 2004, respectively. He was Assistant/Associate Professor at Computer Science Department in the Hong Hong University of Science and Technology, and now Chang Jiang Professor and Dean of School of Software, Tsinghua University, China. Yunhao is the Chair of ACM China Council. He is also serving as the Associate Editor-in-Chief for IEEE Transactions on Parallel and Distributed Systems, and an Associate Editor for IEEE/ACM Transactions on Networking, as well as ACM Transactions on Sensor Networks. He serves many leading conferences as TPC member, such as ACM Mobicom, ACM Mobihoc, IEEE INFOCOM, etc. He is currently an ACM Distinguished Speaker.