Erwan Livolant - Academia.edu (original) (raw)

Papers by Erwan Livolant

2017 1st Cyber Security in Networking Conference (CSNet)

The IoT is a technology that enables the interconnection of smart physical and virtual objects an... more The IoT is a technology that enables the interconnection of smart physical and virtual objects and provides advanced services. Objects or things are generally constrained devices which are limited by their energy, computing and storage capacity. A Wireless Sensor Networks (WSN) is a network composed of devices managed by a CPAN (Personal Area Network Coordinator). The network is used in order to gather and process data of a given environment. It is characterized by their low bit rate and low power consumption, and it uses small size packet in their transmissions. In order to protect the WSN, a mutual authentication between devices is required during the association of a new device. The exchanged data should be authenticated and encrypted. In this work we propose a robust, lightweight and energy-efficient security protocol for the WSN systems. The real tests we made and a performance evaluation of our security protocol are provided.

Studies in Big Data, 2017

2016 IEEE 35th International Performance Computing and Communications Conference (IPCCC), 2016

Most wireless sensor networks that are currently deployed use a technology based on the IEEE 802.... more Most wireless sensor networks that are currently deployed use a technology based on the IEEE 802.15.4 standard. However, this standard does not meet all requirements of industrial applications in terms of latency, throughput and robustness. That is why the IEEE 802.15.4e amendment has been designed, including the Time Slotted Channel Hopping (TSCH) mode. In this paper, we focus on how to build a TSCH network and evaluate the time needed to form the network, using the NS3 simulator. A new beacon advertising algorithm is proposed for TSCH networks. A comparative performance evaluation with solutions already published is done.

Lecture Notes in Computer Science, 2016

Scheduling in an IEEE802.15.4e TSCH (6TiSCH) low-power wireless mesh network can be done in a cen... more Scheduling in an IEEE802.15.4e TSCH (6TiSCH) low-power wireless mesh network can be done in a centralized or distributed way. When using centralized scheduling, a scheduler computes a communication schedule, which then needs to be installed into the network. This can be done using standards such CoAP and CoMI, or using a custom protocol such as OCARI. In this paper, we compute the number of messages installing and updating the schedule takes, using both approaches, on a realistic example scenario. The cost of using today's standards is high. In some cases, a standards-based solution requires approximately 4 times more messages to be transmitted in the network, than when using a custom protocol. This paper makes three simple recommended changes to the standards which, when integrated, reduce the cost of a standardsbased solution by 18% to 74%. Since they are still being developed, these recommendations can easily be integrated into the standards.

Ad Hoc and Sensor Wireless Networks, 2009

Industrials have been increasingly interested in wireless sensor and actuator networks to monitor... more Industrials have been increasingly interested in wireless sensor and actuator networks to monitor and control installations. The recent IEEE 802.15.4 standard has been developed to address vital issues of these networks, such as limited battery power and low processing capabilities. However, the standard does not meet all the requirements of industrial networks. For example, only some of the IEEE 802.15.4 nodes save energy. Also, this standard suffers from beacon frame collisions. In this paper, we describe MaCARI, a deterministic MAC layer protocol which allows all nodes to save energy and avoids the beacon frame collisions. We discuss several optimizations to increase the performance of the protocol or to offer QoS features. We evaluated the main components of MaCARI using a simulation and a prototype on a real hardware platform in order to prove their feasibility.

2015 IEEE International Conference on Wireless for Space and Extreme Environments (WiSEE), 2015

Transactions on Emerging Telecommunications Technologies, 2015

The US Federal Communications Commission (FCC) has mandated wireless network operators and mobile... more The US Federal Communications Commission (FCC) has mandated wireless network operators and mobile devices to provide accurate location information for E-911. Requirements for time of arrival (TOA) and time difference of arrival (TDOA) measurements have been specified in 3GPP LTE Rel. 9 to ensure accurate user equipment (UE) positioning even under bad conditions (e.g. with channel quickly varying and SNR being as low as 13 dB). To fulfil these requirements, it is vital to accurately estimate the first signal arriving path. In this work, we first derive -without any approximationthe Cramér-Rao lower bound (CRLB) of the LTE TOA and TDOA measurements based on the different pilots, which is shown to be as low as a few metres for SNR = 13 dB. The achievable performance of the LTE system is compared with the FCC and 3GPP requirements, and the impact of mobile multipath channels on the measurements is analysed. Then, we describe practical low-complexity methods for LTE TOA and TDOA measurements with enhanced first arriving path detection. The maximum likelihood based correlation profile is used as detection metric. After grossly determining the signal region by a moving window, three methods, namely, peak detection, SNR-based threshold and adaptive threshold based on noise floor and metric peak value are employed to estimate the first arriving path. Simulation results show that the proposed adaptive threshold-based method can meet all 3GPP requirements under various realistic mobile channels, and can in some cases achieve a performance close to the CRLB.

2015 IFIP/IEEE International Symposium on Integrated Network Management (IM), 2015

The new IEEE 802.15.4e standard does not specify how the schedule of medium accesses followed by ... more The new IEEE 802.15.4e standard does not specify how the schedule of medium accesses followed by wireless sensors is built. That is why, we propose a distributed interferenceaware joint channel and time slot assignment, called DiSCA, for a traffic-aware convergecast in multichannel wireless sensor networks (WSNs). Unlike most previous studies, we consider two cases of transmissions: without acknowledgment and with immediate acknowledgment. We provide the minimum bound on the number of time slots needed for a convergecast with a sink equipped with multiple radio interfaces. Simulations results show that DiSCA is close to the optimal in terms of the number of slots and outperforms TMCP.

Proceedings of the 17th ACM international conference on Modeling, analysis and simulation of wireless and mobile systems - MSWiM '14, 2014

IFIP – The International Federation for Information Processing, 2008

Industrials have been increasingly interested in sensor and actuator networks to monitor and cont... more Industrials have been increasingly interested in sensor and actuator networks to monitor and control installations. The recent IEEE 802.15.4 standard has been developed to address vital issues of these networks, such as limited battery power and low processing capabilities. However, the standard does not meet all the requirements of industrial networks. For example, only some of the IEEE 802.15.4 nodes save energy, and the delay for the computer running the monitoring application to retrieve the sensor data or to activate an actuator is not bounded. Our research on energy-efficient MAC protocol is divided into two parts: Part A is the proposal of a flexible, synchronized tree-based MAC protocol called MaCARI and Part B deals with optimizations that can be performed within each cell. This paper focuses on Part A, that is, on the description of the MaCARI protocol. MaCARI is designed to tolerate scheduled activities such as sensor data retrieval and unscheduled activities such as complex routing. MaCARI achieves this flexibility by using a tree-based centralized mechanism. We show the benefits of MaCARI by ensuring all nodes sleep regularly and by proving that the maximum end-to-end delay is bounded.

Journal of Sensor and Actuator Networks, 2013

Convergecast is the transmission paradigm used by data gathering applications in wireless sensor ... more Convergecast is the transmission paradigm used by data gathering applications in wireless sensor networks (WSNs). For efficiency reasons, a collision-free slotted medium access is typically used: time slots are assigned to non-conflicting transmitters. Furthermore, in any slot, only the transmitters and the corresponding receivers are awake, the other nodes sleeping in order to save energy. Since a multichannel network increases the throughput available to the application and reduces interference, multichannel slot assignment is an emerging research domain in WSNs. First, we focus on a multichannel time slot assignment that minimizes the data gathering delays. We compute the optimal time needed for a raw data convergecast in various multichannel topologies. Then, we focus on how to adapt such an assignment to dynamic demands of transmissions (e.g., alarms, temporary additional application needs and retransmissions). We formalize the problem using linear programming, and we propose an incremental technique that operates on an optimized primary schedule to provide bonus slots to meet new transmission needs. We propose AMSA, an Adaptive Multichannel Slot Assignment algorithm, which takes advantage of bandwidth spatial reuse, and we evaluate its performances in terms of the number of slots required, slot reuse, throughput and the number of radio state switches.

2014 6th International Conference on New Technologies, Mobility and Security (NTMS), 2014

In this work, we study raw convergecast in multichannel wireless sensor networks (WSNs) where the... more In this work, we study raw convergecast in multichannel wireless sensor networks (WSNs) where the sink may be equipped with multiple radio interfaces. We propose W ave, a simple and practical distributed joint channel and time slot assignment. We evaluate the number of slots needed to complete the convergecast by simulation and compare it to the optimal schedule and to a centralized solution.

2012 International Conference on Wireless Communications in Underground and Confined Areas, 2012

Wireless sensor networks, WSNs, are an efficient way to deal with low-rate communications in conf... more Wireless sensor networks, WSNs, are an efficient way to deal with low-rate communications in confined environments such as mines or nuclear power plants because of their simplicity of deployment and low cost. In these application domains, WSNs are used to gather data from sensor nodes towards a sink in a multi-hop convergecast structure. In this paper, we focus on a traffic-aware time slot assignment minimizing the schedule length for tree topologies and for two special deployments (i.e. linear and multi-linear) representative of unusual environments. We formalize the problem as a linear program and provide results on the optimal number of slots. We then propose a delay optimized algorithm with two heuristics that minimize on the one hand the energy consumption and on the other hand the storage capacity as secondary criteria.

2012 IEEE 31st International Performance Computing and Communications Conference (IPCCC), 2012

Ridha Soua, Pascale Minet, Erwan Livolant. MODESA: An optimized multichannel slot assignment for ... more Ridha Soua, Pascale Minet, Erwan Livolant. MODESA: An optimized multichannel slot assignment for raw data convergecast in wireless sensor networks.

2013 9th International Wireless Communications and Mobile Computing Conference (IWCMC), 2013

2014 IFIP Wireless Days (WD), 2014

2011 7th International Wireless Communications and Mobile Computing Conference, 2011

The diversity of research topics in Wireless Sensor Networks (WSNs) is attracting more and more r... more The diversity of research topics in Wireless Sensor Networks (WSNs) is attracting more and more researchers from different fields. The common point of all proposed solutions and protocols for WSNs is the evaluation usually done with the network simulators. In this paper, we focus on the results relevance of wireless sensor network simulators in two different scenarios based on indoor and outdoor environments. We propose a comparative study between 3 usual simulators (NS2, OPNET and QualNet) while using as reference a real testbed based on Imote2 sensor platform. Moreover, the impact of different MAC protocols (B-MAC and TKN15.4 MAC) which respect or do not observe the IEEE 802.15.4 standard are illustrated by real experimentations. These experimentations show that TKN15.4 protocol gives a better throughput than B-MAC. In addition, the results obtained from a comparative study between simulators show that 3 of them give different data even in the same environment. The NS2 simulator gives results close to those of the experimentation in the case of an outdoor environment, but in the indoor environment QualNet gives results closer to the reality.

2012 IEEE International Conference on Communications (ICC), 2012

The main goal in wireless sensor networking remains the reduction of the network lifecycle and th... more The main goal in wireless sensor networking remains the reduction of the network lifecycle and the enhancement of its reliability, keeping decent performances in terms of throughput and latency. Given the increasing interest of the research community on wireless network coding (NC), we think such challenges can be tackled using its innovative concepts, especially in the case of many-to-one communications where network coding has shown promising theoretical results. Yet, without a thoughtful adaptation to WSNs, the benefits of NC for sensor networking prove to be too "greedy" and impractical. In this paper, we propose index-coding, a simple and effective packet coding scheme that enhances significantly many-to-one communications in ZigBee sensor networks. Index-coding uses smart bit-shifting operations in order to encode short messages from a set of sensors to a sink using fewer transmissions. Our implementation in a real ZigBee testbed shows substantial enhancement of network performances and resiliency.

2011 IFIP Wireless Days (WD), 2011

In this paper, we propose a new multichannel allocation protocol for ZigBee/IEEE 802.15.4 network... more In this paper, we propose a new multichannel allocation protocol for ZigBee/IEEE 802.15.4 networks. The main goal is to improve the global throughput which is basically insufficient to satisfy high bandwidth requirements for applications like monitoring or traffic control. The solution is based on the availability of multiple channels on current lowcost, low-energy radio transceivers, such as CC2420, which can be easily tuned dynamically to different frequencies. This possibility can be exploited to increase the number of simultaneous transmissions on adjacent links. The allocation of the different channels is centralized and distributed by the coordinator thanks to a function designed to compute the channel offset between two successive children routers. In the nodes, the switching process between the transmission and the reception channels is triggered starting from the PHY primitive available on the transceiver. The evaluation shows that the proposed protocol improves the global throughput by a factor between 2 and 5, depending on the scenario, compared to the single-channel solution or a random channel allocation.