Embedded intelligent systems are gradually becoming common in our everyday lives by offering means to measure and control our surrounding environment. This expansion is coupled with an increasing diversity in electronic systems in terms of communication protocols (Wi-Fi, Bluetooth, IEEE 802.15.4...), size, user interface, processing power, memory, energy source and sensing/actuating capabilities. Interconnecting such heterogeneous devices is a real challenge, which today requires a strong expertise in several technological domains.
The design of a software component in between the user application, the operating system and sometimes the actual hardware itself, known as « middleware », facilitates the application development for complex and heterogeneous sensor networks. Existing middlewares answer this need in a limited manner.
This PhD thesis, funded by the Walloon First DoCA program, aims to provide a simple and coherent application interface harnessing the flexibility and configurability of underlying technologies and protocols to achieve end goals such as minimal energy consumption of a network, or the support for device mobility. Furthermore, in light of the Future Internet initiatives and the upcoming Internet of Things, this thesis has a strong focus on the interconnection of networked objects to the Internet and common consumer devices such as smartphones and tablets. These innovations will contribute to facilitate the design of applications with impacts that will reshape the world as we know it today.
In 2011, CETIC studied the implementation and deployment of WSN application based on technologies current in standardisation, such as 6LoWPAN and RPL, IETF’s IPv6 Routing Protocol for Low Power and Lossy Networks. These studies were made possible thanks to a development cycle comprised of three distinct test environments: a software time-accurate simulator for wireless sensor networks (COOJA), physical sensor platforms part of CETIC’s Wireless Lab, and large-scale academic wireless sensor testbeds open for experimentations. In particular, the SensLAB testbed of INRIA Lille and the TWIST testbed of TU-Berlin are crucial for studying the impact of Radio Duty Cycling (RDC), a key enabler for network longevity, on the stability of RPL and the embedded IPv6 stack of Contiki. These testbeds also allow the study of the scalability of such protocols in two respects: total node count, and node density. These topics answer to vision of the Internet of Things of tomorrow, which will likely involve the interconnection of a potentially large number of smart objects, with hard constraints on device memory, processing power and power consumption. In fall 2011, CETIC initiated a collaboration with SICS, the founder of the Open Source Contiki OS, through a 3-month intership at Stockholm. This on-going collaboration will lead to the publication of scientific results in 2012 in international wireless sensor network workshops and conferences.
Added-value for Businesses
This research project has a direct impact for local Walloon companies keen to integrate Internet of Things solutions in their products. As of today, CETIC’s expertise is already guiding companies in design choices for sensor network hardware and software. In the future, middleware components developed in Contiki and other operating systems will be made available in the public domain, with CETIC as an enabler for technological transfer.