Keynote Lectures

Energy Efficient Sensor Network Configuration for Covering Points of Interest
Christos Douligeris, University of Piraeus, Greece

Sensor Networks, Where Theory Meets Practice
Roger Wattenhofer, , Switzerland

Energy Efficient Sensor Network Configuration for Covering Points of Interest

Christos Douligeris
University of Piraeus
Greece

Brief Bio
Christos Douligeris, currently a professor at the department of Informatics, University of Piraeus, Greece held positions with the Department of Electrical and Computer Engineering at the University of Miami. He was an associate member of the Hellenic Authority for Information and Communication Assurance and Privacy. Dr. Douligeris has published extensively in the networking scientific literature and he has participated in many research and development projects. He is the co-editor of a book on ‘‘Network Security’’ published by IEEE Press/ John Wiley and he is on the editorial boards of several scientific journals as well as on the technical program committees of major international conferences. His main research interests lie in the areas of communications, networking security, medical informatics and emergency response operations.

Abstract
A critical problem in wireless sensor networks research and application is the efficient handling of the nodes' energy under the point of interest (PoI) coverage constraint. Since the sensors are randomly deployed in the field some PoIs are covered only by a few sensors. Thus, the maximum achieved network lifetime is upper bounded by the energy of the sensors that cover the most poorly covered targets. In this talk, we tackle this problem by either dividing the nodes in sets so that only one set is active at any time or by moving some sensors to poorly covered areas from areas that are covered by many sensors. The first approach is mathematically proven to be an NP-complete problem so sub-optimal solutions, like centralised or localised heuristics are proposed. The second approach requires the use of mobile nodes to move from one PoI to another and may drain the nodes energy when the distance between the PoIs is high. Advantages and disadvantages of the two approaches will be discussed.

Sensor Networks, Where Theory Meets Practice

Roger Wattenhofer

Switzerland

Brief Bio

Roger Wattenhofer is a full professor at the Information Technology and Electrical Engineering Department, ETH Zurich, Switzerland. He received his doctorate in Computer Science in 1998 from ETH Zurich. From 1999 to 2001 he was in the USA, first at Brown University in Providence, RI, then at Microsoft Research in Redmond, WA. He then returned to ETH Zurich, originally as an assistant professor at the Computer Science Department.

Roger Wattenhofer's research interests are a variety of algorithmic and systems aspects in computer science and information technology, currently in particular wireless networks, wide area networks, mobile systems, social networks, and physical algorithms. He publishes in different communities: distributed computing (e.g., PODC, SPAA, DISC), networking (e.g., SIGCOMM, MobiCom, SenSys), or theory (e.g., STOC, FOCS, SODA, ICALP).

Abstract
Researchers in wireless multi-hop networks are used to studying some of the prevalent technical difficulties in networking. Without a dependable fixed infrastructure, challenges such unreliable wireless communication must be investigated in their purest form. As a consequence, one learns a great deal about the theoretical principles of networking when examining wireless sensor networks. In my talk I will present a few exciting research questions that I learned when studying sensor networks: I will discuss how practical network dynamics lead to the theory of distributed complexity, why multi-hop clock synchronization is unexpectedly difficult both in theory and practice, and what difference it makes to assume a more accurate wireless model.