Thomas Watteyne

Proposition of a hard real-time MAC protocol for wireless sensor networks

Many wireless sensor network applications are emerging nowadays. For critical, safety related applications, the network needs to provide bounded transmission delays. Hard real-time guarantees need therefore to be given by wireless sensor network communication protocols. In this paper, we propose a new hard real-time MAC protocol, and we give the time constraints that can be reached.

Centroid virtual coordinates - A novel near-shortest path routing paradigm

Geographic routing has received increasing attention in the context of Wireless Sensor Networks since it frees the network from the energy-demanding task of building and maintaining a structure. It requires however each node to know its position, which may be a prohibitive assumption for many applications. To this end, some prior work has focused on inferring a nodes location from a set of location-aware anchor nodes. In this work, we free ourselves from positioning techniques and anchor nodes altogether, and introduce and analyze the concept of virtual coordinates. These coordinates are chosen randomly when a node is switched on, and are updated each time the node relays a packet. As this process goes on, the virtual coordinates of the nodes converge to a near-optimal state. When using a greedy geographic approach on top of these coordinates, we show that the number of hops to reach the destination exceeds the shortest path by a few percent only. Moreover, our approach guarantees delivery even when nodes appear/disappear in the network, and under realistic transmission models. We analytically prove the correctness of our protocol. Moreover, extensive simulations are used to show that our position-free solution outperforms existing geographic protocols - such as Greedy-Face-Greedy (GFG) or Greedy Perimeter Stateless Routing (GPSR) - in terms of energy-efficiency, path length and robustness.

Interoperability, Safety and Security in IoT

This book constitutes the refereed post-conference proceedings of the Third International Conference on Interoperability, InterIoT 2017, which was collocated with SaSeIoT 2017, and took place in Valencia, Spain, in November 2017. The 14 revised full papers were carefully reviewed and selected from 22 submissions and cover all aspects of the latest research findings in the area of Internet of Things (IoT)

Using virtual coordinates for wireless sensor networks: Proof-of-concept experimentation

Routing in a multi-hop wireless network with lowcost nodes is still a challenging task, and specific ultra-low power solutions need to be investigated for WSNs. Geographic routing protocols have been designed, analyzed and simulated. Yet, early experimental trials show that they fail dramatically when faced with real-world constraints such as lossy links. Experimental studies are needed as a complement to analysis and simulation.