[Show abstract][Hide abstract] ABSTRACT: In collaborative wireless networks with a low infrastructure, the presence of misbehaving nodes can have a
negative impact on network performance. In particular, we are interested in dealing with this nasty presence in
road safety applications, based on Vehicular Ad hoc Networks (VANETs). Because of its characteristics, namely
high mobility, frequent topology changes, and large deployment areas, verifying safety data validity is difficult, and
existing solutions to tackle this issue are inefficient in VANETs. In this work, we consider as harmful the presence of malicious nodes, which spread false and forged data; and selfish nodes, which cooperate only for their own benefit. To deal with this, we propose DTM2, a Distributed Trust Model, adapted from the Job Market Signaling Model. DTM2 is based on allocating credits to nodes and securely managing these credits. To motivate selfish nodes to cooperate more, our solution establishes the cost of reception to access data, forcing them to earn credits. Moreover, to detect and exclude malicious nodes, DTM2 requires the cost of sending, using signaling values inspired form economics and based on the node’s behavior, so that the more a node is malicious, the higher its sending cost, thus limiting their participation in the network. Similarly, rewards are given to nodes whose sent messages are considered as truthful, and that paid a sending cost considered as correct. The latter is a guarantee for the receivers about the truthfulness of the message since, in case of message refusal, the source node is not rewarded despite its payment. We validated DTM2 via a theoretical study using Markov chains; and with a set of simulations, in both urban and highway scenarios. Both theoretical and simulation results show that DTM2 excludes from the network 100% of malicious nodes, without causing any false positive detection. Moreover, our solution guarantees a good ratio of reception even in the presence of selfish nodes.
IEEE Transactions on Vehicular Technology 09/2014; · 2.06 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The increasing interest about the Internet of Things (IoT) is almost as remarkable than its practical absence in our everyday lives. Announced as the new breakthrough in IT industry, the domain is characterized by a large number of architecture propositions that are in charge of providing a structure for applications creation. These architectures are needed because of the heterogeneity of stakeholders involved in IoT Applications. Programming languages, operating systems, hardware specificities, processing power, memory, network organization, characteristics, constraints, the world of IoT is so diverse. Furthermore, these architectures should provide an easy access to users that are not aware of IT technologies involved. The Services Oriented Computing (SOC) has shown in the past its relevance to the decoupling constraints interoper-ability among stakeholders. The composition of loosely coupled services facilitates the integration of very varied elements and provides agility in the creation of new applications. But unlike the approach inherited from the SOC in pre-existing services are composed to obtain a specific application, we propose a more dynamic notion of service. Our "Object-as-a-Service" point of view is based on the notion of building dynamically the service needed on each Object and then integrate it in the whole composition. This paper focus on the gain of this approach for the IoT by promoting the "Object-as-a-Service" paradigm as a basis for the creation of dynamic and agile user-made applications. I. INTRODUCTION With the spread of wireless communications and the rise of the number of devices capable of processing data, the idea of connecting everything to everything, through the universal medium offered by the Internet, opens the way to a new era in the computing domain, usually called the "Internet of Things". The "Major trends in computing", as defined by M. Weiser  has occurred. At the beginning, the "mainframe" era (one computer for many users), followed by the "personal" era (one computer for one person), we are now entering the "ubiquitous" computing era (many computers for one user). Desktop computers, laptops, but also smartphones, palm, internet Boxes, and now connected TVs, household appliances, phydgets, single-board micro-computers, we are surrounded by "intelligent" objects, able to process data, communicating through networks, and hav-ing new capabilities of sensing or acting on the real world. The main idea of the Internet of Things is to expand the network, extending it into houses, buildings (walls, floor, windows, doors, etc.) and cities (car park, traffic light, lights, etc.). After its connection to offices, then homes, the Internet
Global Information Infrastructure and Networking Symposium - GIIS 2014 -, Montréal; 09/2014
[Show abstract][Hide abstract] ABSTRACT: The increasing interest about the Internet of Things (IoT) is almost as remarkable than its practical absence in our everyday lives. Announced as the new breakthrough in IT industry, the domain is characterized by a large number of architecture propositions that are in charge of providing a structure for applications creation. These architectures are needed because of the heterogeneity of stakeholders involved in IoT Applications. Programming languages, operating systems, hardware specificities, processing power, memory, network organization, characteristics, constraints, the world of IoT is so diverse. Furthermore, these architectures should provide an easy access to users that are not aware of IT technologies involved. The Services Oriented Computing (SOC) has shown in the past its relevance to the decoupling constraints interoper-ability among stakeholders. The composition of loosely coupled services facilitates the integration of very varied elements and provides agility in the creation of new applications. But unlike the approach inherited from the SOC in pre-existing services are composed to obtain a specific application, we propose a more dynamic notion of service. Our "Object-as-a-Service" point of view is based on the notion of building dynamically the service needed on each Object and then integrate it in the whole composition. This paper focus on the gain of this approach for the IoT by promoting the "Object-as-a-Service" paradigm as a basis for the creation of dynamic and agile user-made applications.
Global Information Infrastructure and Networking Symposium - GIIS 2014 -; 08/2014
[Show abstract][Hide abstract] ABSTRACT: Facilitating the creation of Internet of Things (IoT) applications is a major concern to increase its de-velopment. D-LITe, our previous work, is a framework for that purpose. In D-LITe, Objects are considered as part of a whole application. They offer a REST web service that describes Object capabilities, receives the logic to be executed, and interacts with other stakeholders. Then, the complete application is seen as a choreography dynamically deployed on various objects. But the main issue of choreographies is the loss of coherence. Because of their unreliability, some networks used in IoT may introduce de-synchronization between Objects, leading to errors and failures. In this paper, we propose a solution to re-introduce coherence in the application, in order to keep the advantages of choreography while dealing with this main issue. An overlay of logical check-points at the application layer defines links between the coherent states of a set of objects and triggers re-synchronization messages. Correcting statements are thus spread through the network, which enables fault recovery in Choreographies. This paper ends with a comparison between the checking cost and the reliability improvement.
[Show abstract][Hide abstract] ABSTRACT: Service Oriented Computing (SOC) is a common way to build applications/services by composing distributed bricks of logic. Recently, the SOC paradigm has been considered for the design and implementation of Internet of Things (IoT) applications by abstracting objects as service providers or consumers. Based on this trend, we proposed in a previous work D-LITe: a lightweight RESTful virtual machine that allows ubiquitous logic description and deployment for IoT applications using Finite State Transducers (FST). Though D-LITe allows faster and more efficient application creation for heterogeneous objects, it turns out that FST design can be fastidious for inexperienced users. With that in mind, we propose in this paper BeC
3 (Behaviour Crowd Centric Composition) an innovative crowd centric architecture, grounded on D-LITe. It provides a simpler way to compose interactions between IoT components. The idea is to reverse the bottom-up approach of SOC by a rather top-down vision in which the user expresses the expected result of his application by composing behaviours that are proposed by contributors. These behaviours are deployed on each concerned component, which then act exactly as needed to fulfil their role in the composition. The crowd-Centric aspect of this platform allows a community-based design, granting a wide panel of modular and incremental interactions for a wide variety of components. Eventually, BeC
3 will give inexperienced users the ability to organise, interconnect and compose both state of the art web-services and IoT components to create interactive 2.0-like applications for the IoT.
Mobile Networks and Applications 02/2014; 19(1):18-32. · 1.11 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The Long Term Evolution (LTE) standard is one
of the most promising technologies of wireless network for
the development of Machine-to-Machine (M2M) communication
because of its high data rates, low latency, high flexibility and
low cost. However, improvements are needed in the network to
support the uplink-heavy traffic generated by M2M communication
and also to ensure the diversity of service requirements
of this communication. The uplink packet scheduler is included
in the necessary improvements. In this article, we evaluate the
performance of the main schedulers for M2M communication
regarding the aspects of service requirements, fairness, energy
efficiency and impact on the system performance of current LTE
[Show abstract][Hide abstract] ABSTRACT: This paper proposes a mechanism for uplink packet scheduler in LTE network in the context of Machine-to-Machine (M2M) communication. The proposed approach uses the current and past information of the system to satisfy the Quality of Service (QoS) requirements, to ensure fairness in resource allocation and to control the congestion caused by M2M devices. We carried out some network simulations by using a NS-3 simulator so as to show the effectiveness of the proposed approach. The results indicate that our solution can reduce the impact of M2M communication on Human-to-Human (H2H) communication and avoid the problem of starvation, when compared to related approaches.
[Show abstract][Hide abstract] ABSTRACT: This paper proposes a mechanism for uplink packet scheduler in LTE
network in the context of Machine-to-Machine (M2M) communications that uses
the current and past information of the system to satisfy the Quality of Service
(QoS) requirements, ensure fairness in the allocation of resources and control
the congestion caused by the M2M devices. The results indicate that the proposed
approach can reduce the impact of M2M communication on the Human-to-
Human (H2H) communication and avoid the problem of starvation.
32º Simpósio Brasileiro de Redes de Computadores e Sistemas Distribuídos – SBRC 2014; 01/2014
[Show abstract][Hide abstract] ABSTRACT: The primary contribution of this paper is the design of a novel architecture and mechanisms to enable voice services to be deployed over femtocells backhauled using a wireless mesh network. The architecture combines three mechanisms designed to improve Voice Over IP (VoIP) call quality and capacity in a deployment comprised of meshed-femtocells backhauled over a WiFi-based Wireless Mesh Network (WMN), or femto-over-mesh. The three mechanisms are: (i) a Call Admission Control (CAC) mechanism employed to protect the network against congestion; (ii) the frame aggregation feature of the 802.11e protocol which allows multiple smaller frames to be aggregated into a single larger frame; and (iii) a novel delay-piggy-backing mechanism with two key benefits: prioritizing delayed packets over less delayed packets, and enabling the measurement of voice call quality at intermediate network nodes rather than just at the path end-points. The results show that the combination of the three mechanisms improves the system capacity for high quality voice calls while preventing the network from accepting calls which would result in call quality degradation across all calls, and while maximizing the call capacity available with a given set of network resources.
2013 IEEE 24th International Symposium on Personal, Indoor and Mobile Radio Communications: Mobile and Wireless Networks (PIMRC'13 - Mobile and Wireless Networks); 09/2013
[Show abstract][Hide abstract] ABSTRACT: Machine Type Communication (MTC) is an essential service for next generation cellular networks. Because of the massive number of communicating devices, MTC poses great challenges for Radio Access Network (RAN). This is mainly caused by the overloading problem that has been aggressively addressed by 3GPP as an essential working item. Because of this overloading problem, classical Human to Human (H2H) communications may be negatively affected. In this paper we first introduce the MTC and its challenges with a focus on its use in the healthcare domain. The Random Access procedure (RACH) used in Long Term Evolution (LTE) cellular networks will be then explained in order to address the issue of RACH overload coming from massive number of MTC devices. To resolve RAN overload, 3GPP and others have proposed several RAN solutions. We evaluate and compare these solutions and conclude finally with their advantages and weaknesses in order to select the best solution for an operator.
2013 2nd International Conference on Advances in Biomedical Engineering (ICABME); 09/2013
[Show abstract][Hide abstract] ABSTRACT: As the Internet of Things (IoT) grows in interest from both research and industrial parts, the lack of standard solutions to quickly and easily build and install IoT applications becomes a topic of high interest. In this paper, we introduce a language called SALT (Simple Application Logic description using Transducers) that allows describing and deploying the distributed logic needed in order to fulfil a complete desired application. This language aims at giving extended functionalities by filling the gap between the logical capabilities offered by services orchestration and the closeness efficiency of services choreography. SALT is interpreted by a virtual machine running on devices that introduces an abstraction layer in order to simplify access to hardware capabilities. SALT implements several mechanisms to comply with organisation issues presented in the Services Oriented Computing realm dealing with Services interactions, adapted to the specific constraints of the IoT. This work details SALT's concepts, formalism and implementation.
IEEE International Conference on Communications - Communication Software and Services Symposium (ICC'13 CSS); 06/2013
[Show abstract][Hide abstract] ABSTRACT: Geographic routing protocols use location information when they need to route packets. In the meantime, location information are maintained by location-based services provided by network nodes in a distributed manner. Routing and location services are very related but are used separately. Therefore, the overhead of the location-based service is not considered when we evaluate the geographic routing overhead. Our aim is to combine routing protocols with location-based services in order to reduce communication establishment latency and routing overhead.
Our main contribution is to reduce the location overhead. Thus, we propose two combinations: (1) a geographic routing protocol with GLS called Hybrid Routing and Grid Location Service (HRGLS) and (2) a geographic routing protocol with HLS denoted Hybrid Routing and Hierarchical Location Service (HRHLS), where instead of launching an exact position request, we send the packet to the old destination position and when the packet is approaching the former position, we request the exact one.
The complexity of the location query cost in both proposed schemes is O(logN)O(logN), while it is O(N) in the case of HLS and GLS. Simulation results also confirm the complexity analysis and show promising results in terms of latency, packet delivery ratio and control message overhead.
Journal of Parallel and Distributed Computing 01/2013; · 1.12 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The high node mobility in Vehicular Ad-hoc Networks (VANETs) leads to frequent topology changes and link breaks. Geographic routing protocols are more suitable for these networks where the use of position-to-position paradigm to forward data. We need to know the destination position usually given by an external service denoted as a location-based service. However, geographic routing protocols and location-based services are often implemented separately and are not gathered. In this paper, we discuss a coupling mechanism of geographic routing protocols and hierarchical location-based services. We have implemented this mechanism under the NS-2 simulator. We have shown the reduction of the location-based service overhead. In the meantime, the packet delivery ratio and the average end-to-end delay have been improved.
Broadband and Wireless Computing, Communication and Applications (BWCCA), 2013 Eighth International Conference on; 01/2013
[Show abstract][Hide abstract] ABSTRACT: The IEEE 802.15.4 protocol is widely adopted as the standard for the physical and MAC layers of wireless sensor networks. Among other mechanisms, it implements a mechanism called duty cycle that defines the node's active time during the network lifetime. This paper proposes a dynamic beacon interval and superframe adaptation algorithm (DBSAA) that adjusts the network duty cycle through two MAC layer parameters: the Beacon Order (BO) and the Superframe Order (SO). The parameters adaptation is triggered by the changes in the traffic load (i.e. increase or decrease due to modification in the environment). Using DBSAA, the network coordinator adjust the BO and SO parameters based on four parameter estimations: the superframe occupation ratio, the collision ratio, the number of packets received by the coordinator, and the number of source nodes. Performance evaluation results show that the duty cycle adaptation taking into account the BO and SO values meets the trade-off defined by the application requirements and energy consumption while compared to two other protocols: the standard 802.15.4 protocol, which does not perform duty cycle dynamic adaptation; and the DSAA (Dynamic Superframe Adjustment Algorithm), which adapts the duty cycle by adjusting only the SO parameter.
Global Information Infrastructure Symposium, 2013; 01/2013
[Show abstract][Hide abstract] ABSTRACT: Wireless Mesh Networks (WMNs) are becoming increasingly popular and user demand for high-quality rich media services is continuously growing. Despite the fact that WMNs offer significant flexibility, they suffer in respect to Quality of Service (QoS) provisioning. This paper proposes a novel mechanism for providing enhanced QoS support to video services in multi-hop WMNs. The mechanism makes use of an innovative hybrid hierarchical architecture which combines centralized and distributed approaches. The proposed solution relies on performance monitoring at WMN nodes and performs load balancing by off-loading traffic from the highest loaded nodes to less loaded neighbours. Simulation-based results presented outline the performance of our proposed mechanism in terms of QoS metrics (delay, throughput, packet losses and PSNR) in different network load scenarios. The results clearly demonstrate how our proposed mechanism outperforms the traditional OLSR protocol in terms of QoS performance.
High Performance Switching and Routing (HPSR), 2013 IEEE 14th International Conference on; 01/2013
[Show abstract][Hide abstract] ABSTRACT: In this body of work, we are interested in road safety applications such as advanced driver assistance systems, based on Vehicular Ad hoc Networks (VANETs). One of the particular characteristics of this kind of networks is the continuous sharing of safety information by its nodes. Since this kind of information is time sensitive, a node cannot spend much time to verify its validity with an authority. However, the presence of malicious and selfish nodes in VANETs corrupts exchanged data, and lowers the overall data reception ratio in the network. To tackle this, we propose a new incentive model with exclusion for malicious nodes called VIME. VIME is inspired from the signaling theory from economics. It is based on managing a credit count that each node receives at the initialization of the application. Straightforwardly, VIME is based on two pillars. On the one hand, a node pays an appropriate cost for each sent message, which is seen by the receivers as a guarantee from the source about the truthfulness of the information. On the other hand, nodes get rewarded for cooperating in the network. The proposed economic model allows computing the amounts to be paid and those to be awarded in order to fight selfish and malicious nodes. We validate our approach via simulations. We show that VIME is able to detect and evict gradually all malicious nodes in the network, and decreases the ratio of corrupted and false sent data until reaching zero. Moreover, it has a positive impact on the participation of selfish nodes, as our approach increases the average ratio of sent data as to equal the ideal case's percentage, when no selfish node is present.
Computing, Communications and IT Applications Conference (ComComAp), 2013; 01/2013
[Show abstract][Hide abstract] ABSTRACT: Location-based services provide (and maintain) location information used by geographic routing protocols. Routing and location service are widely related, but handled separately in usual studies about Vehicular Ad hoc Network (VANET). In this paper, we propose a hybrid approach, denoted mobility-Prediction-based Hybrid Routing and Hierarchical Location Service (PHRHLS), coupling a VANET routing protocol, the Greedy Perimeter Stateless Routing (GPSR), and the Hierarchical Location Service (HLS) extended with a mobility prediction algorithm. We show that our approach, PHRHLS, reduces the localization overhead and enhances the routing performances. Indeed, our extensive simulations show promising results in terms of end-to-end latency, packet delivery ratio and control message overhead.
Communications (ICC), 2013 IEEE International Conference on; 01/2013
[Show abstract][Hide abstract] ABSTRACT: Wireless Sensor and Actuator Networks (WSAN) and permanent connections to the Internet converge to be an emerging and promising field: Machine-To-Machine (M2M) services. To take advantages of this new field, hardware and software infrastructure compliance must be verified. Services expected by M2M alter the organization of WSAN. The software design in this area can be divided into two main categories: a centralized approach (Orchestration) where a monolithic application collects data and sends orders, and a distributed approach (Choreography) in which nodes offer and use services in a collaborative way. In this paper, we study the impact of these two architectures over WSAN. First, a mathematical analysis shows the improvement offered by choreography, thanks to the use of shorter paths between nodes. Then, an application experiments these two architectural designs to measure the impact on a real testbed. Both the theoretical mathematical analysis and the real platform experiment gives better results for the Choreography in terms of network reliability and path length. Our work quantifies the benefits obtained and provides histograms and numerical results.
17th IEEE Symposium on Computers and Communications (ISCC'12); 07/2012