Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 965 Experimental Challenges in Wireless Sensor Networks – Environment, Mobility, and Interference OLOF RENSFELT ACTA UNIVERSITATIS UPSALIENSIS ISSN 1651-6214 ISBN 978-91-554-8448-4 UPPSALA urn:nbn:se:uu:diva-179807 2012 Dissertation presented at Uppsala University to be publicly examined in Polhemssalen, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, Friday, October 12, 2012 at 13:15 for the degree of Doctor of Philosophy. The examination will be conducted in English. Abstract Rensfelt, O. 2012. Experimental Challenges in Wireless Sensor Networks – Environment, Mobility, and Interference. Acta Universitatis Upsaliensis. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 965. 172 pp. Uppsala. ISBN 978-91-554-8448-4. Wireless sensor networks are used to collect sensor data in different applications such as environmental monitoring, smart building control, and health care applications. Wireless sensor nodes used are typically small, low-cost, and battery powered. The nodes are often hard to access after deployment, for example when they are in remote locations. Another property of wireless sensor networks is that their operation is dependent on the environment they operate in, both due to the specific sensor readings but also due to the effects on communication by factors such as fading and radio interference. This makes it important to evaluate a wireless sensor network in its intendent target environment before final deployment. To enable experiments with wireless sensor networks in their target environment, we have designed and implemented a testbed called Sensei-UU. It is designed to allow WSN experiments to be repeated in different locations, thus exposing effects caused by the environment. To allow this, the testbed is designed to be easily moved between experimental sites. One type of WSN applications Sensei-UU is aimed to evaluate is protocols where nodes are mobile. Mobile testbed nodes are low-cost robots which follow a tape track on the floor. The localization accuracy of the robot approach is evaluated and is accurate enough to expose a protocol to fading phenoma in a repeatable manner. Sensei-UU has helped us develop a lightweight interference classification approach, SoNIC, which runs on standard motes. The approach only use information from a standard cc2420 chipset available when packets are received. We believe that the classification accuracy is good enough to motivate specific transmission techniques avoiding interference. Keywords: Wireless Sensor Networks, Testbed, Mobility, Interference classification Olof Rensfelt, Uppsala University, Department of Information Technology, Computer Systems, Box 337, SE-751 05 Uppsala, Sweden. © Olof Rensfelt 2012 ISSN 1651-6214 ISBN 978-91-554-8448-4 urn:nbn:se:uu:diva-179807 (http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-179807) Dedicated to all hard-working torcedores and coffee farmers List of papers This thesis is based on the following papers, which are referred to in the text by their Roman numerals. I Olof Rensfelt, Lars-Åke Larzon, and Sven Westergren, “Vendetta - A Tool for Flexible Monitoring and Management of Distributed Testbeds.” In proceedings of 3rd IEEE International Conference on Testbeds and Research Infrastructures for the Development of Networks and Communities (TRIDENTCOM), 2007. II Olof Rensfelt, Frederik Hermans, Lars-Åke Larzon, and Per Gunningberg, “Sensei-UU: A Relocatable Sensor Network Testbed.” In the fifth ACM International Workshop on Wireless Network Testbeds, Experimental evaluation and Characterization (Wintech), 2010 © 2010 Association for Computing Machinery, Inc. Reprinted by permission. http://doi.acm.org/10.1145/1860079.1860091 III Olof Rensfelt, Frederik Hermans, Per Gunningberg, Lars-Åke Larzon and Erik Björnemo, “Repeatable Experiments with Mobile Nodes in a Relocatable WSN Testbed” In The Oxford Computer Journal, Volume 54, Number 12 (The Computer Journal 2011) IV Frederik Hermans, Olof Rensfelt, Lars-Åke Larzon, and Per Gunningberg, “A Light-weight Approach to Online Detection and Classification of Interference in 802.15.4-based Sensor Networks” In the ACM SIGBED Review, Special Issue on the Third International Workshop on Networks of Cooperating Object, Volume 9, Number 3, 2012 V Olof Rensfelt, Frederik Hermans, Thiemo Voigt, Edith Ngai, Lars-Åke Nordén, and Per Gunningberg, “SoNIC: Classifying and Surviving Interference in 802.15.4-based Sensor Networks” Technical Report 2012-022, Department of Information Technology, Uppsala University, 2012. Reprints were made with permission from the publishers. Other work In addition to the papers above, the following papers, posters, demos and workshops, represent work that I have participated in, presented, authored or co-authored. • Olof Rensfelt, Richard Gold, and Lars-Åke Larzon. “LUNAR over Blue- tooth.“ In Proceedings of the 4th Scandinavian Workshop on Wireless Ad-Hoc Networks (ADHOC 2004). • Christian Tschudin, Richard Gold, Olof Rensfelt, and Oskar Wibling. “LUNAR - A Lightweight Underlay Network Ad-hoc Routing Protocol and Implementation.“ In Next Generation Teletraffic and Wired/Wireless Advanced Networking (NEW2AN’04), TTY Paino, Tampere, Finland, p 300, 2004. • Olof Rensfelt and Lars-Åke Larzon. “Addressing heterogenity in peer to peer networks” In the 2nd Swedish National Computer Networking Workshop (SNCNW 2004) • Olof Rensfelt and Lars-Åke Larzon. “A bandwidth study of a DHT in a heterogeneous environment.” it:2007-017, ISSN 1404-3203, Techni- cal Report 2007-017, Department of Information Technology, Uppsala University, May 2006. • Sven Westergren, Olof Rensfelt, and Lars-Åke Larzon.“NoteNet” In the 4th Swedish National Computer Networking Workshop (SNCNW 2006) • Olof Rensfelt and Lars-Åke Larzon. “A bandwidth study of a DHT in a heterogeneous environment” In the 4th Swedish National Computer Networking Workshop (SNCNW 2006) • Sven Westergren, Peter Drugge, Olof Rensfelt and Lars-Åke Larzon. “NoteNet.” In the 4th Annual International Conference on Mobile Sys- tems, Applications and Services - Demonstration (MobiSys 2006) Upp- sala, Sweden. • Olof Rensfelt, Lars-Åke Larzon, and Sven Westergren.“Dtour - An Ap- proach to Reproducibility on PlanetLab” ACM SIGCOMM Conference on Applications, Technologies, Architectures, and Protocols for Com- puter Communications - Poster (SIGCOMM 2007) August 2007, Kyoto, Japan. • Olof Rensfelt, Frederik Hermans, Christofer Ferm, Per Gunningberg, Lars-Åke Larzon. “Building a Testbed for Heterogeneous Wireless Sen- sor Networks” In the 6th Swedish National Computer Networking Work- shop (SNCNW 2008) • Olof Rensfelt, Frederik Hermans, Christofer Ferm, Per Gunningberg, and Lars-Åke Larzon. “An Interactive Testbed for Heterogeneous Wire- less Sensor Networks.” In the 4th IEEE International Conference on Distributed Computing in Sensor Systems (DCOSS 2008) demo pro- ceedings: June 2008, Santorini, Greece. • Olof Rensfelt, Lars-Åke Larzon, Christofer Ferm, Frederik Hermans and Per Gunningberg. “SENSEI - a nomadic testbed with support for mo- bility” In the 7th Swedish National Computer Networking Workshop (SNCNW 2009) • Olof Rensfelt, Frederik Hermans,Christofer Ferm, Per Gunningberg, and Lars-Åke Larzon. “Sensei-UU: A Nomadic Sensor Network Testbed Supporting Mobile Nodes” it:2009-025, ISSN 1404-3203,Technical Re- port 2009-025, Department of Information Technology, Uppsala Univer- sity, October 2009. • Olof Rensfelt, Joel Samuelsson, Frederik Hermans, Per Gunningberg, Lars-Åke Larzon. “Playing Pacman with Sensei-UU: A relocatable testbed with support for mobile nodes”, The 8th Annual International Conference on Mobile Systems, Applications and Services, demonstra- tion proceedings (MobiSys 2010) June 2010, San Francisco, USA - Best demonstration award • Olof Rensfelt, Frederik Hermans, Per Gunningberg, and Lars-Åke Lar- zon “Repeatable Experiments with Mobile Nodes in a Relocatable WSN Testbed.” In the first International Workshop on Mobility in Wireless Sensor Networks (MobiSensor 2010) June 2010, Santa Barbara, USA. • Navid Hassanzadeh, Olaf Landsiedel, Frederik Hermans, Olof Rensfelt, Thiemo Voigt “Efficient Mobile Data Collection with Mobile Collect.” In the 8th IEEE International Conference on Distributed Computing in Sensor Systems (DCOSS 2012) May 2012, Hangzhou, China • Navid Hassanzadeh, Thiemo Voigt, Olaf Landsiedel, Frederik Hermans, Olof Rensfelt. “Do Sensor Networks Need Mobile MAC Protocols?” In the 3rd International Workshop on Networks of Cooperating Objects, (Conet 2012) April Beijing, China • Hjalmar Wennerström, Frederik Hermans, Olof Rensfelt, Christian Rohner, Lars-Åke Larzon. “A Long-Term Study on the Effects of Meteorological Conditions on 802.15.4 Links” In the 8th Swedish National Computer Networking Workshop (SNCNW 2012), June 2012, Stockholm, Swe- den. Implementations • mLUNAR. A light weight, multi hop ad hoc routing protocol that runs on Lego Mindstorms. It tunnels TCP/IP traffic over infrared. It was demoed at Mobicom 2002. • BTLUNAR. A port of LUNAR, a reactive ad hoc routing protocol, to run over the Linux Bluetooh stack BlueZ. • Bamboo for NS2. An implementation of the overlay network Bamboo for NS2. • Sensei-UU. A relocatable WSN testbed with support for mobile nodes. Contents 1 Introduction ................................................................................................ 15 1.1 Wireless Sensor Networks ............................................................