ECRTS08

7th International Workshop on Real-Time Networks RTN'08

Prague, Czech Republic, July 1, 2008

in conjunction with the

20th Euromicro Intl Conference on Real-Time Systems
Prague, Czech Republic, July 2 - 4, 2008

Workshop Chair

Anis Koubâa

Research affiliation
IPP-HURRAY Research Group, ISEP-IPP, (Portugal)
Teaching affiliation
Al-Imam Muhammad Ibn Saud University
College of Computer Science and
Information Systems
11681 Riyadh (Saudi Arabia)

Email - Homepage

 

Program Committee
  • Mohamed Abid
    (University of Sfax, Tunisia)
  • Luis Almeida
    (University of Aveiro, Portugal)
  • Jean-Dominique Decotignie
    (Swiss Center for Microtechnology, Switzerland)
  • Sameh Gobriel
    (Intel Corporation, USA)
  • Tian He
    (University of Minnesota, USA)
  • Lucia Lo Bello
    (University of Catania, Italy)
  • Daniel Mossé
    (University of Pittsburgh, USA)
  • Paolo Pagano
    (RETIS Lab, Italy)
  • Shashi Prabh
    (IPP -HURRAY!, Portugal)
  • Jens B. Schmitt
    (University of Kaiserslautern, Germany)
  • Ye-Qiong Song
    (LORIA - Nancy University - INPL, France)
  • Thiemo Voigt
    (Swedish Institute of Computer Science, Sweden)
  • Andreas Willig
    (Technical University of Berlin, Germany)

Important Deadlines

  • Submission of papers: 24 April 2008
  • Notification of acceptance: 26 May 2008
  • Submission of updated papers: 14 June 2008
  • Broadcast of papers: 20 June 2008
  • RTN Workshop: 1 July 2008
  • Euromicro Conf. on RTS: 2-4 July 2008
  • Final versions: 8 September 2008

Previous Editions

 

Real-Time and Wireless Sensor Networks :
Why do we need another view at it ?

Speaker: Pr. Jean-Dominique Decotignie

Professor at EPFL & Swiss Center for Microtechnology, Switzerland

Time: 9:30 - 10:30

Abstract

Networking at the sensory level is now very common. Fieldbusses have been around for more than 2 decades They can be found in many types of application such as factory automation, process plants, car automation or building automation. Since the first solutions were designed in the early 80s, a number of proposals have flourished and the field is well established both in terms of research and industrial use. Most solutions use wired transmission (twisted pairs, coaxial cables, optical fibers) and provide real-time guarantees at different degrees. Establishing these guarantees has been the subject of a number of papers in previous issues of this workshop.
Using wireless transmission at the sensory level is very attracting. It has been employed for years to link mobile robots or automated guided vehicles to control and supervision computers. At the fieldbus level, a number of solutions have been proposed. The Esprit Project OLCHFA designed in 1992 a full wireless network based on the FIP protocol. LON offers some wireless transceivers that can be used to built a mixed wired / wireless network. The same applies to the first version of the IEC fieldbus. Wireless extensions to Profibus were studied within the R-Fieldbus IST project. Wireless HART is now an established solution in the process control domain.
Wireless sensor networks have emerged at the very beginning of this century as a separate subject leading to a huge quantity of publications with little concern about time. More recently, temporal issues are starting to interest researchers and there are a few proposals claiming real-time support such as IEEE 802.15.4.
It is tempting to reuse in the WSN context the solutions that were developed to construct real-time fieldbusses and the techniques that we employed to analyze the temporal properties. There are however fundamental differences between the propagation properties on cable and in the wireless case. Two of them are the probability that a message is not received correctly and the path losses. Wireless transmission suffers from much higher BER and higher attenuations. While the latter is taken into account in most solutions, the former is mostly ignored when dealing with real-time properties. For instance, papers keep stating that pure TDMA or IEEE 802.15.4 offer real-time guarantees because they avoid collisions. This is true in absence of transmission error, an assumption that does not hold in the wireless domain.
It is easy to show that hard real-time bounds are impossible to guarantee in wireless communications. There is thus a need to find another way to define the real-time properties of wireless sensor networks. The talk will explore some of these ways and also explain why pure TDMA is probably a bad solution to support real-time guarantees.

Pr. Jean-Dominique Decotignie: Short Biography

Jean-Dominique Decotignie is head of the real-time software and networking group at the Centre Suisse d’Electronique et de Microtechnique SA (CSEM) in Neuchatel. He is also adjunct professor at the Ecole Polytechnique Fédérale de Lausanne (EPFL). From 1977 to 1982, he has worked at EPFL and the University of Tokyo in the area of optical communications. In 1983, he joined the Industrial Computer Engineering Lab. at EPFL where he became Assistant Professor in 1992. From 1989 to 1992, he has been the head of an interdisciplinary project o Computer Integrated Manufacturing at EPFL. Since January 1997, he is with CSEM. His current research interests include real-time networks and self-organising wireless sensor networks as well as software engineering and middleware for real-time systems. Dr. Decotignie received his MS in 1977 and PhD in 1982 both in electrical engineering from the EPFL. He is an IEEE fellow. Besides his publication record (more than 100 papers in international journals and conferences), Dr. Decotignie has a long experience in leading development and research projects. Between 1989 and 1992, he has led the development of an automatic flexible manufacturing and assembly shop (40 engineers and technicians). From 1992 to 1996, he co-directed the Industrial Computer Engineering laboratory at EPFL (35 researchers). Since, he has a led a number of industrial projects at CSEM and has been WP leader in half a dozen European projects including Integrated Projects.