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showing 10 items of 2747 documents
UAV Communication Strategies in the Next Generation of Mobile Networks
2020
| openaire: EC/H2020/857031/EU//5G!Drones The Next Generation of Mobile Networks (NGMN) alliance advocates the use of different means to support vehicular communications. This aims to cope with the massive data generated by these devices which could affect the Quality of Service (QoS) of the associated applications, but also the overall operation carried out by the vehicles. However, efficient communication strategies must be considered in order to select, for each vehicle, the communication mean ensuring the best QoS. In this paper, we tackle this issue and we propose efficient communication strategies for Unmanned Aerial Vehicles (UAVs). In addition to direct UAV-to-Infrastructure communi…
Blockchain Based Delegatable Access Control Scheme for a Collaborative E-Health Environment
2018
Modern electronic healthcare (e-health) settings constitute collaborative environments requiring sophisticated fine-grained access control mechanisms to cater their access demands. Access delegatability is quite crucial to realize fine-grained, flexible access control schemes compatible with such environments. In this paper, we addressed this issue through proposing an attribute based access control scheme integrated with controlled access delegation capabilities suitable for a multi-domain e-health environment. We have utilized the blockchain technology to manage attribute assignments, delegations as well as revocations. The scheme enables delegations in a controlled manner without jeopard…
5G Functional Architecture and Signaling Enhancements to Support Path Management for eV2X
2019
Enhanced vehicle-to-everything (eV2X) communication is one of the most challenging use cases that the fifth generation (5G) of cellular mobile communications must address. In particular, eV2X includes some 5G vehicular applications targeting fully autonomous driving which require ultra-high reliability. The usual approach to providing vehicular communication based on single-connectivity transmission, for instance, through the direct link between vehicles (PC5 interface), often fails at guaranteeing the required reliability. To solve such a problem, in this paper, we consider a scheme where the radio path followed by eV2X messages can be proactively and dynamically configured to either trans…
Priority-based initial access for URLLC traffic in massive IoT networks: Schemes and performance analysis
2020
Abstract At a density of one million devices per square kilometer, the10’s of billions of devices, objects, and machines that form a massive Internet of things (mIoT) require ubiquitous connectivity. Among a massive number of IoT devices, a portion of them require ultra-reliable low latency communication (URLLC) provided via fifth generation (5G) networks, bringing many new challenges due to the stringent service requirements. Albeit a surge of research efforts on URLLC and mIoT, access mechanisms which include both URLLC and massive machine type communications (mMTC) have not yet been investigated in-depth. In this paper, we propose three novel schemes to facilitate priority-based initial …
Optimal Buffer Resource Allocation in Wireless Caching Networks
2019
Wireless caching systems have been exhaustively investigated in recent years. Due to limited buffer capacity, and unbalanced arrival and service rates, the backlogs may exist in the caching node and even cause buffer overflow. In this paper, we first investigate the relationship among backlogs, buffer capacity, data arrival rate and service rate, utilizing the martingale theory which is flexible in handling any arrival and service processes. Then given a target buffer overflow probability, the minimal required buffer portion is determined. If the devoted buffer capacity can fulfill all serving users' minimal buffer requirements, an optimization problem is constructed with the objective to m…
A symbolic distributed event detection scheme for Wireless Sensor Networks
2016
Due to the possibility of extensive and pervasive deployment of many tiny sensor devices in the area of interest, Wireless Sensor Networks (WSNs) result particularly suitable to detect significant events and to react accordingly in industrial and home scenarios. In this context, fuzzy inference systems for event detection in WSNs have proved to be accurate enough in treating imprecise sensory readings to decrease the number of false alarms. Besides reacting to event occurrences, the whole network may infer more information to enrich the event semantics resulting from reasoning processes carried out on the individual nodes. Contextual knowledge, including spatial and temporal relationships, …
Embedding Evolution in Epidemic-Style Forwarding
2007
International audience; In this work, we introduce a framework to let forwarding schemes evolve in order to adapt to changing and a priori unknown environments. The framework is inspired by genetic algorithms: at each node a genotype describes the forwarding scheme used, a selection process fosters the diffusion of the fittest genotypes in the system and new genotypes are created by combining existing ones or applying random changes. A case study implementation is presented and its performance evaluated via numerical simulations.
Performance analysis of the out-of-band signaling scheme for high speed wireless LANs
2005
In this paper, we study the performance of our earlier proposed out-of-band signaling (OBS) scheme for high speed wireless local area networks (WLANs). We employ the system approximation technique for modeling of the OBS scheme. An equivalent state dependent single server queue, that describes the OBS scheme, is constructed for the analysis of the throughput and delay performances. Moreover, we study the throughput optimization of the OBS scheme, which provides a means for optimizing the performance of the OBS scheme, given a particular network environment. Finally, we conduct several simulation experiments to validate our analytical results.
Call Admission Control in Single and Two-Tier Cellular Networks
2010
We consider four strategies for call admission control (CAC) in single and two-tier cellular networks, which are designed to ensure advantage of handover calls: dynamic redundancy (cutoff priority scheme), partial dynamic redundancy (fractional guard channel scheme), static redundancy (rigid division-based CAC scheme) and restriction of the number of new calls admitted (new call bounding scheme). We show the advantage of dynamic reservation by numerical analysis. We strictly prove it in the case of two-channel system with losses.
An attribute based access control scheme for secure sharing of electronic health records
2016
Electronic health records (EHRs) play a vital role in modern health industry, allowing the possibility of flexible sharing of health information in the quest of provisioning advanced and efficient healthcare services for the users. Although sharing of EHRs has significant benefits, given that such records contain lot of sensitive information, secure sharing of EHRs is of paramount importance. Thus, there is a need for the realization of sophisticated access control mechanisms for secure sharing of EHRs, which has attracted significant interest from the research community. The most prominent access control schemes for sharing of EHRs found in literature are role based and such solutions have…