Predictable and Dependable Low-power Wireless Networks

February 3, 2015
Marco Zimmerling | ETH Zurich

By integrating components for sensing, communicating, computing, and actuating, Cyber-Physical Systems (CPSs) enable applications to monitor and control physical processes. The use of wireless, battery-powered devices unlocks tangible benefits in these emerging CPS settings. However, wireless communications is notoriously unreliable, and small form factors and battery-powered operation impose constraints on the computation and communication capabilities. These issues present severe threats to CPSs, whose safety-critical nature calls for two key features from the networking substrate: (1) predictability at design time, to analyze the behavior of the system before it is deployed, and (2) dependability at run-time, to ensure the correct functioning of the system despite failures. So, in this talk, I will pose the following question: Is it possible to provide predictable and dependable end-to-end communication guarantees on top of unreliable multi-hop low-power wireless networks?

I will explain why it is impractical to address this question using conventional low-power wireless stacks, and describe our work on designing and building a clean-slate communication architecture from the ground up to overcome this problem. In particular, the proposed architecture provides real-time and virtual-synchrony guarantees on the end-to-end delivery of messages – features that were previously deemed impossible to achieve in these networks. Real-time communication is crucial for the correctness of many CPSs, and virtual synchrony enables the design of fault-tolerant CPSs using state machine replication. Moreover, the architecture allows for predicting the network’s end-to-end performance using simple models with unprecedented accuracy, which can greatly aid in the design and verification of CPSs.

Speaker Details

Marco Zimmerling is a PhD student in Computer Engineering at ETH Zurich, Switzerland. He holds a master’s degree with a major in Computer Science and a minor in Mathematics from Dresden University of Technology, Germany. In 2006, Marco did a six-month internship at the IBM T.J. Watson Research Center in Hawthorne, USA. In 2009, he spent seven months in Sweden to write his master’s thesis in collaboration with researchers at SICS Swedish ICT and Uppsala University. Marco’s current research interests are in networked embedded systems, with a focus on enabling predictable and dependable operation on individual platforms and across multi-hop low-power wireless networks. Marco’s work has been recognized through several awards, including the Best Paper Award at ACM SenSys 2013, the Best Paper Award at ACM/IEEE IPSN 2011, the Best Paper Runner-up at ACM/IEEE IPSN 2012, and the SensorNets 2009 Best M.Sc. Thesis Award. More info at http://www.tik.ee.ethz.ch/~marcoz/