Georgios Z. Papadopoulos

• PhD
• Professor (Associate) at IMT Atlantique

The Internet of Things (IoT) technology is growing rapidly, while the IoT devices are being deployed massively. However, interoperability with information systems remains a major challenge for this accelerated device deployment. Furthermore, most of the time, IoT information is presented as Time Series (TS), and while the majority of the studies in...

The Internet of Things (IoT) makes it possible to connect devices with reduced processing capacities to the network, using wireless communications links. These technologies are particularly useful for improving the control and monitoring of industrial processes, as they make it possible to deploy sensors and actuators, often battery‐powered ones, m...

This chapter addresses cyberdefense techniques for the Internet of Things (IoT) based on the Moving Target Defense (MTD) paradigm. It presents general concepts from classical MTD literature and some related works. The chapter summarizes MTD techniques for the IoT and identifies potential MTD solutions for the IoT. The MTD cyberdefense paradigm is b...

IEEE Std 802.15.4-2015 Time Slotted Channel Hopping (TSCH) is the de facto Medium Access Control (MAC) mechanism for industrial applications. It renders communications more resilient to interference by spreading them over the time (time-slotted) and the frequency (channel-hopping) domains. The 6TiSCH architecture bases itself on this new MAC layer...

The Battery Management System of an Electric Vehicle is a system designed to ensure safe operation of the battery pack, and report its state to other systems. It is a distributed system, and the communication between its sub-modules is performed through wired buses. In this article, we study the opportunity to use a wireless technology named IEEE S...

L’Internet des objets (en anglais Internet of Things, IoT), aujourd’hui omniprésent, a grandement contribué à l’accroissement du trafic des données sur Internet. Les technologies d’accès IoT et les contraintes des objets peuvent causer des problèmes de performances et de sécurité. Cela démontre l’importance des défis liés à cet environnement comme...

L’Internet des objets (en anglais Internet of Things, IoT), aujourd’hui omniprésent, a grandement contribué à l’accroissement du trafic des données sur Internet. Les technologies d’accès IoT et les contraintes des objets peuvent causer des problèmes de performances et de sécurité. Cela démontre l’importance des défis liés à cet environnement comme...

Integrated Access and Backhaul (IAB) allows to ease the deployment of gNodeBs (gNBs) in a 5G network by connecting them using cellular connectivity. The radio frequencies to achieve such a result can be the same as the ones used to connect User Equipment (UE) (in-band) or specific ones can be reserved (out-of-band). Both sub 6 GHz and millimeter wa...

RÉSUMÉ Dans le cadre de ses activités de consultations, ONIRIS offre, via des lunettes connectées, une téléexpertise auprès des vétérinaires ruraux. Ce service donne au vétérinaire, lors de ses consultations, accès en temps réel voix et vidéo à un expert situé dans son lieu de travail devant son ordinateur afin de guider le vétérinaire dans son int...

The emergence of the IoT has made wireless connectivity ubiquitous and necessary. Extending the IoT to the IIoT places significant demands in terms of reliability on wireless connectivity. The Institute of Electrical and Electronics Engineers (IEEE) Std 802.15.4-2015 standard was designed in response to these demands, and the 6LoWPAN adaptation lay...

The Internet of Things (IoT) has become ubiquitous due to its flexibility, ease-of-use, and reduced cost. As a consequence, the industry is adopting these systems in its transformation into Industry 4.0. However, the strict Quality of Service (QoS) requirements of the industry are not met with the default best-effort provisions of the IoT. Most ind...

Internet of things consist in the deployment of constrained and battery-powered devices with a radio interface. Most industrial applications require to respect strict reliability and delay constraints. Lossy links imply mechanisms to retransmit the packets to improve the reliability. However, transient faults (e.g. obstacles, interference) may also...

Wireless communication is a key technology for the Internet of Things (IoT). Due to its open nature, the physical layer of wireless systems is a high-priority target for an adversary whose goal is to disrupt the normal behavior of the system. In particular, jamming attacks are one of the most straightforward and effective types of attacks: informat...

Context: Internet of Things (IoT) systems are increasingly deployed in the real world, but their security lags behind the state of the art of non-IoT systems. Moving Target Defense (MTD) is a cyberdefense paradigm, successfully implemented in conventional systems, that could improve IoT security. Objective: Identify and synthesize existing MTD tech...

Due to uncontrolled interferences, including the self-induced multi-path fading, deterministic networking is difficult to achieve on wireless links. The radio conditions may change much faster than a centralized routing paradigm can adapt and reprogram, in particular when the controller is distant and connectivity is slow and limited. Reliable and...

The Internet Engineering Task Force (IETF) Low Power Wide Area Network (LPWAN) Working Group has developed the Static Context Header Compression (SCHC) framework to enable IPv6 over LPWAN. In order to support 1280-byte packets, as required for IPv6, SCHC includes a fragmentation functionality, since relevant LPWAN technologies offer very short data...

The Internet of Things (IoT) is driving research and innovation in the areas of security and device management. The bootstrapping procedure is yet another security problem that needs to be solved. At the bootstrapping period, a newly deployed device is performing a set of actions that allows it to join a network as a trusted party. One of the curre...

The Industrial Internet of Things (IIoT) is expected to be a key enabler for the Industry 4.0. However, networked control automation often requires high reliability and a bounded latency to react properly. Thus, modern wireless protocols for industrial networks, such as IEEE 802.15.4-2015 Time Slotted Channel Hopping (TSCH), rely on a strict schedu...

With the large adoption of small and smart objects, the Internet of Things (IoT) enables a large and universal access over a very heterogeneous set of devices. More specifically, the Industrial IoT (IIoT) aims to provide a wireless infrastructure for industrial applications, relying on time‐critical flows. However, radio communications are known to...

Though the requirements are well defined and established, the adoption of radios for mission critical applications is lagging due to the fuzzy transmission characteristics of the wireless medium. To enable automation and safety applications, in particular for Machine‐to‐Machine traffic, strict reliability and availability demands must be met end‐to...

IEEE std 802.15.4‐2015 Time Slotted Channel Hopping (TSCH) extends and replaces multiple proprietary industrial standards to support ultra‐reliable and ultra‐low power operation in Industrial Internet of Things. Under TSCH, all devices must remain continuously synchronised with their time source neighbour. To do so, the nodes either periodically ex...

LoRa is a popular low-rate, Low-Power Wide Area Network (LPWAN) technology providing long range wireless access over unlicensed sub-GHz frequency bands to the Internet of Things (IoT). It has been used in many applications ranging from smart building to smart agriculture. LoRa is a patented modulation. However preliminary reverse-engineering effort...

Low Power Wide Area Networks (LPWANs) have emerged as new networks for Internet of Things (IoT). LPWANs are characterized by long-range communications and low energy consumption. Furthermore, LPWAN technologies have a small data unit and do not provide a fragmentation mechanism. To enable these technologies to support IPv6 and, thus, be compliant w...

Several Internet of Things (IoT) applications have strict performance requirements, in terms of reliability and power consumption. IEEE 802.15.4 Time Slotted Channel Hopping (TSCH) is a recently standardised Medium Access Control (MAC) protocol that supports these requirements by keeping the nodes time-synchronised. In order to ensure successful co...

Several Internet of Things (IoT) applications have strict performance requirements, in terms of reliability and power consumption. IEEE 802.15.4 Time Slotted Channel Hopping (TSCH) is a recently standardised Medium Access Control (MAC) protocol that supports these requirements by keeping the nodes time-synchronised. In order to ensure successful co...

LoRa is a popular low-rate, low-power wide area network technology providing long range wireless access over unlicensed sub-GHz frequency bands to the Internet of Things (IoT). It has been used in many applications ranging from smart building to smart agriculture. LoRa is a patented modulation, but preliminary reverse-engineering efforts documented...

In 2005, IPv6 over Low Power WPAN (6LoWPAN), the first Working Group (WG) on the Internet of Things (IoT), was established in the Internet Engineering Task Force (IETF) to standardize mechanisms to transmit IPv6 datagrams over IEEE 802.15.4 technology. Since IPv6 may contain datagram sizes much larger than the IEEE 802.15.4 maximum frame size, a ne...

The IPv6 Routing Protocol for Low-Power and Lossy Networks (RPL) is designed for Internet of Things (IoT) applications. This Low Power and Lossy Network (LLN) protocol builds a Destination Oriented Directed Acyclic Graph (DODAG) network by transmitting DODAG Information Object (DIO) control packets. The DODAG structure created is hierarchical, wher...

Industrial applications require more and more low-power operation and high-reliability (close to 100%). Since traditional low-power radio technologies are sensitive to external interference, many recent standards implement frequency hopping schemes. For instance, IEEE 802.15.4-2015 Time Slotted Channel Hopping (TSCH) relies on a deterministic sched...

More and more industrial applications require high reliability while relying on low-power devices for their flexibility. Unfortunately, radio transmissions are prone to unreliability and are very sensitive to external interference. Therefore, a great amount of effort has been put into channel hopping approaches, which help to combat external interf...

Important changes in electricity consumption model require a communication network within the electrical grid, which is called the Advanced Metering Infrastructure (AMI) that can handle the increase of multiple and fluctuating production sites. Recently, we witness the convergence of this communication network and the electricity network into what...

The Industrial Internet of Things (IIoT) faces multiple challenges to achieve high reliability, low-latency and low power consumption. The IEEE 802.15.4 Time-Slotted Channel Hopping (TSCH) protocol aims to address these issues by using frequency hopping to improve the transmission quality when coping with low-quality channels. However, an optimized...

The first Internet Engineering Task Force (IETF) Working Group (WG) on Internet of Things (IoT), IPv6 over Low power WPAN (6LoWPAN), was established in 2005 to enable mechanisms to transmit Internet Protocol version 6 (IPv6) packets over IEEE 802.15.4. Since IPv6 supports packet sizes larger than the IEEE 802.15.4 maximum frame size, 6LoWPAN WG def...

This demonstration defines a small IoT wireless network that uses TI CC2538-OpenMote as hardware platform and state-of-the-art IETF network standards such as 6LoWPAN, RPL, and CoAP implemented by ContikiOS. The IoT nodes are controlled from outside the IoT network using end-to-end connectivity provided by IPv6-CoAP messages. We implement a man-in-t...

IPv6 Routing Protocol for Low-Power and Lossy Networks (RPL) is a distance vector routing protocol especially designed for the Internet of Things (IoT). RPL uses broadcast DODAG Information Object (DIO) messages to build a Destination Oriented Directed Acyclic Graph (DODAG) toward a root. Each node selects a parent node toward the root using a comm...

In this demo, we present a framework to retrieve data from an electric vehicle platform and publish it through an embedded wireless network. We developed driver programs to read the car’s data (such as speed, battery level, etc.), and we built a IEEE802.15.4-TSCH network with a (CoAP) server to make it available to other devices. We also developed...

Wireless industrial applications require high level of Quality of Service (QoS) such as low-delay and jitter performances, low-power operations as well as end-to-end reliability close to 100%. However, considering the large number of wireless networks operating in 2.4 GHz, the radio technologies are more prone to the external interference, which ev...

Wireless industrial networks require reliable and deterministic communication. Determinism implies that there must be a guarantee that each data packet will be delivered within a bounded delay. Moreover, it must ensure that the potential congestion or interference will not impact the predictable properties of the network. In 2016, IEEE 802.15.4-Tim...

LoRa networks enable long range communications for Internet of Things (IoT) applications. The current LoRa technology provides a wide range of communication settings whereas many combination settings are orthogonal and, thus, they can be successfully decoded at the gateway when the signals are transmitted simultaneously. Previous simulation results...

The IEEE 802.15.4 Time Slotted Channel Hopping (TSCH) networks suffer considerably from the high interference caused by the presence of nearby external devices, such as from the presence of IEEE 802.11b/g/n Access Points. Frequency hopping and blacklisting of radio channels that temporarily or consistently present bad performance are the two main a...

Industrial applications require more and more low-power operations, low-delay, deterministic communications as well as end-to-end reliability close to 100%. IEEE 802.15.4-TSCH (Time-Slotted Channel Hopping) relies on a channel hopping technique while scheduling properly the transmissions to provide a high end-to-end reliability. Because of external...

Envisioned communication densities in Internet of Things (IoT) applications are increasing continuously. Because these wireless devices are often battery powered, we need specific energy efficient (low-power) solutions. Moreover, these smart objects use low-cost hardware with possibly weak links, leading to a lossy network. Once deployed, these Low...

This book constitutes the refereed proceedings of the 16th International Conference on Ad-hoc, Mobile, and Wireless Networks, ADHOC-NOW 2018, held in St. Malo, France, in September 2018. The 21 full and 6 short papers plus 2 invited talks presented in this volume were carefully reviewed and selected from 52 submissions. The contributions were organ...

Industrial applications require more and more low-power operations, low-delay, deterministic communications as well as end-to-end reliability close to 100%. However, traditional radio technologies are sensitive to external interference, which degrades the reliability and introduces unpredictable delays due to collision detection and retransmissions...

The previous years saw the emergence of Electric Vehicles (EVs) and Charging Stations (CSs). In such deployments, energy-efficiency and optimal energy distribution are some of the most essential parameters to address, as on-time demand for supplying energy to EVs must be fulfilled. Nowadays several standards exist in the community. In this paper, a...

Advance clustering techniques have been widely used in Wireless Sensor Networks (WSNs) since they can potentially reduce latency, improve scheduling, decrease end-to- end delay and optimise energy consumption within a dense network topology. In this paper, we present a novel clustering algorithm for high density IEEE 802.15.4-2015 Time-Slotted Chan...

In this paper, we explore the role of simulators and testbeds in the development procedure of protocols or applications for Wireless Sensor Networks (WSNs) and Internet of Things (IoT). We investigate the complementarity between simulation and experimentation studies by evaluating latest features available among open testbeds (e.g., energy monitori...

La volonté d'utiliser l'Internet des Objets dans le secteur de l'industrie offre de nouvelles perspectives pour développer des technologies standardsàstandards`standardsà bas cout, mais exigé egalement des extensions et adaptationsàadaptations`adaptationsà ces nouveaux applicatifs. Les standards actuels reposent sur des systèmes de détection d'erre...

With the ubiquity of sensing technologies in our personal spaces, the protection of our privacy and the confidentiality of sensitive data becomes a major concern. In this paper, we focus on wearable embedded systems that communicate data periodically over the wireless medium. In this context, we demonstrate that private information about the physic...

Recent boom of mobile applications has become an essential class of mobile Internet of Things (IoT), whereby large amounts of sensed data are collected and shared by mobile sensing devices for observing phenomena such as traffic or the environmental. Currently, most of the proposed Medium Access Control (MAC) protocols mainly focus on static networ...

Performance analysis of newly designed solutions is essential for efficient Internet of Things and Wireless Sensor Network (WSN) deployments. Simulation and experimental evaluation practices are vital steps for the development process of protocols and applications for wireless technologies. Nowadays, the new solutions can be tested at a very large...

Time Slotted Channel Hopping (TSCH) is among the proposed Medium Access Control (MAC) layer protocols of the IEEE 802.15.4-2015 standard for low-power wireless communications in Internet of Things (IoT). TSCH aims to guarantee high network reliability by exploiting channel hopping and keeping the nodes time-synchronized at the MAC layer. In this pa...

Time Slotted Channel Hopping (TSCH) is among the Medium Access Control (MAC) schemes defined in the IEEE 802.15.4-2015 standard. TSCH aims to guarantee high-level network reliability by keeping nodes time-synchronised. In order to ensure successful communication between a sender and a receiver, the latter starts listening shortly before the expecte...

In scenarios involving point-to-multipoint network traffic, transmitting to each destination individually with unicast may lead to poor utilisation of network bandwidth, excessive energy consumption caused by the high number of packets and suffers from low scalability as the number of destinations increases. An alternative approach, would be to use...

While more and more deployments of Wireless Sensor Networks (WSNs) are successful, very few are actually mobility-aware. Due to their intermittent connectivity, mobile nodes induce certain instabilities, and thus, require to transmit multiple data packets in a short period of time. The nature of mobile nodes can lead to a link quality deterioration...

Verification of theoretical analysis is a vital step to the development of an application or a protocol for wireless networks. Most of proposals are evaluated through mathematical analysis followed by either simulation or experimental validation campaigns. In this paper, we analyze a large set of statistics on articles published (i.e. 674 papers in...

In Wireless Sensor Networks (WSNs), during the design of Medium Access Control (MAC) protocols, mobile nodes may pose many communication challenges. These difficulties require first a link establishment between a mobile and static node, and then an efficient and effective data packet transmissions. In this study, we propose MobiXplore, a MAC scheme...

Reliable data packet transfer is an essential facet of quality of service in Wireless Sensor Networks (WSNs). WSNs require pertinent and reliable data collection schemes to provide dependable information. We analyze the factors that affect reliability, and design efficient combinations of the possible options. While many researchers have tackled th...

The Internet of Things brings unique constraints and a huge variety of applications. This forces to be able to establish energy efficient communications (and nevertheless low-delay) within highly dynamic networks. We focused on improving the medium access control (MAC) to optimize the management of wireless communications, the main source of energy...

This demonstration aims at observing in an interactive manner the impact of modification of preamble and sampling periods at the low-power family of MAC protocols, and thus, illustrating in real-time the energy consumption and delay performance of each node accordingly. To do so, we implemented the ability for users to generate traffic at some remo...

This article aims at observing in an interactive manner the impact of modification of preamble and sampling periods at the low-power family of MAC protocols, and thus, illustrating in real-time the energy consumption and delay performance of each node accordingly. To do so, we implemented the ability for users to generate traffic at some remote nod...