Internet of Drones Simulator: Design, Implementation, and Performance Evaluation

The Internet of Drones (IoD) is a networking architecture that stems from the interplay between Unmanned Aerial Vehicles (UAVs) and wireless communication technologies. Networked drones can unleash disruptive scenarios in many application domains. At the same time, to really capitalize their potential, accurate modeling techniques are required to catch the fine details that characterize the features and limitations of UAVs, wireless communications, and networking protocols. To this end, the present contribution proposes the Internet of Drones Simulator (IoD-Sim), a comprehensive and versatile open source tool that addresses the many facets of the IoD. IoD-Sim is a Network Simulator 3 (ns-3)-based simulator organized in a 3-layer stack, composed by (i) the Underlying Platform, which provides the telecommunication primitives for different standardized protocol stacks, (ii) the Core, that implements all the fundamental features of an IoD scenario, and (iii) the Simulation Development Platform, mainly composed by a set of tools that speeds up the graphical design for every possible use-case. In order to prove the huge potential of this proposal, three different scenarios are presented and analyzed from both a software perspective and a telecommunication standpoint. The peculiarities of this open-source tool are of interest for researchers in academia, as they will be able to extend to model upcoming specifications, including, but not limited to, mobile networks and satellite communications. Still, it will certainly be of relevance in industry to accelerate the design phase, thus improving the time-to-market of IoD-based services.Comment: in IEEE Internet of Things Journal, 202

A Frequency Domain Model to Predict the Estimation Accuracy of Packet Sampling

International audienceIn network measurement systems, packet sampling techniques are usually adopted to reduce the overall amount of data to collect and process. Being based on a subset of packets, they hence introduce estimation errors that have to be properly counteracted by a fine tuning of the sampling strategy and sophisticated inversion methods. This problem has been deeply investigated in the literature with particular attention to the statistical properties of packet sampling and the recovery of the original network measurements. Herein, we propose a novel approach to predict the energy of the sampling error on the real time traffic volume estimation, based on a spectral analysis in the frequency domain. We start by demonstrating that errors due to packet sampling can be modeled as an aliasing effect in the frequency domain. Then, we exploit this theoretical finding to derive closed-form expressions for the Signal-to-Noise Ratio (SNR), able to predict the distortion of traffic volume estimates over time. The accuracy of the proposed SNR metric is validated by means of real packet traces

AIMD and CCN: Past and Novel Acronyms Working Together in the Future Internet

http://conferences.sigcomm.org/co-next/2012/workshops/CSWS/International audienceContent-centric networking (CCN) is a new paradigm to better handle contents in the future Internet. Under the assumption that CCN networks will deploy a similar congestion control mechanism than in today's TCP/IP (i.e., AIMD), we can build an analytical model of the bandwidth sharing in CCN based on the "square-root formula of TCP'". With this model we compare CCN download performance to what users get today. We consider different factors such as the way CCN routers are deployed, the popularity of contents, or the capacity of links and observe that when AIMD is used in a CCN network less popular content throughput is massively penalized whilst the individual gain for popular content is negligible. Finally, the main advantage of using CCN is the decrease of load at the server side. Our observations advocate the necessity to clearly define the notion of fairness in CCN and to design a proper congestion control to avoid less popular contents to become hardly accessible in tomorrow's Internet

CCN-TV: a data-centric approach to real-time video services

International audienceContent-Centric Networking (CCN) is a promising data-centric architecture, based on in-network caching, name-driven routing, and receiver-initiated sessions, which can greatly enhance the way Internet resources are currently used, making support for a broader set of users with increasing traffic demands possible. The CCN vision is, currently, attracting the attention of many researchers across the world, since it has all the potential to become ready to the market, to be gradually deployed in the Internet of today, and to facilitate a graceful transition from a host-centric networking rationale to a more effective data-centric working behaviour. At the same time, several issues have to be investigated before CCN can be safely deployed at the Internet scale. They include routing, congestion control, caching operations, name-space planning, and application design. With reference to application-related facets, it is worth noticing that the demand for TV services is growing at an exponential rate over time, thus requiring a very careful analysis of their performance in CCN architectures. To this end, in the present contribution we deploy a CCNTV system, capable of delivering real-time streaming TV services, and we evaluate its performance through a simulation campaign based on real-world topologies

Providing crowd-sourced and real-time media services through a NDN-based platform

International audienceThe diffusion of social networks and broadband technologies is letting emerge large online communities of people that stay always in touch with each other and exchange messages, thoughts, photos, videos, files, and any other type of contents. At the same time, due to the introduction of crowd-sourcing strategies, according to which services and contents can be obtained by soliciting contributions from a group of users, the amount of data generated and exchanged within a social community may experience a radical increment never seen before. In this context, it becomes essential to guarantee resource scalability and load balancing to support real time media delivery. To this end, the present book chapter aims at investigating the design of a network architecture, based on the emerging Named Data Networking (NDN) paradigm, providing crowd-sourced real-time media contents. Such an architecture is composed by four different entities: a very large group of heterogeneous devices that produce media contents to be shared, an equally large group of users interested in them, a distributed Event Management System that creates events and handles the social community, and a NDN communication infrastructure able to efficiently manage users requests and distribute multimedia contents. To demonstrate the effectiveness of the proposed approach, we have evaluate its performance through a simulation campaign using real-world topologies

Exercise stress testing in clinical practice

Exercise stress testing is an important diagnostic tool for evaluating patient’s cardiovascular performance. The present review describes the accuracy and the value of exercise stress testing in different settings: after an acute coronary event, after percutaneous coronary intervention or coronary artery bypass graft; in patients risk assessment before non-cardiac surgery; in diabetic population; in patients with baseline electrocardiographic abnormalities. Moreover, this review provides insights relating to test accuracy in women and geriatric patients. Finally, this review explores new variables/parameters (dyspnea, chronotropic incompentence, heart rate recovery, functional capacity, integrated scores) that in the last few years added an incremental value to conventional analysis of exercise-induced angina or electrocardiographic changes

Social Cooperation for Information-Centric Multimedia Streaming in Highway VANETs

Abstract-High-quality multimedia streaming services in Vehicular Ad-hoc Networks (VANETs) are severely hindered by intermittent host connectivity issues. The Information Centric Networking (ICN) paradigm could help solving this issue thanks to its new networking primitives driven by content names rather than host addresses. This unique feature, in fact, enables native support to mobility, in-network caching, nomadic networking, multicast, and efficient content dissemination. In this paper, we focus on exploring the potential social cooperation among vehicles in highways. An ICN-based COoperative Caching solution, namely ICoC, is proposed to improve the quality of experience (QoE) of multimedia streaming services. In particular, ICoC leverages two novel social cooperation schemes, namely partner-assisted and courier-assisted, to enhance information-centric caching. To validate its effectiveness, extensive ns-3 simulations have been executed, showing that ICoC achieves a considerable improvement in terms of start-up delay and playback freezing with respect to a state-of-the-art solution based on probabilistic caching

Energy harvesting in LoRaWAN: a cost analysis for the industry 4.0

Exploiting the advantages brought by long-range radio communications and extremely low power consumptions, LoRaWAN is capable to support low rate industry 4.0 services. Despite being energy efficient, LoRa motes can still undergo frequent battery replenishments caused by the monitoring requirements of industrial applications. Duty-cycle constrained operations can partially face this issue at the expense of increased communication delays, which, in turn, inflate higher costs due to damaged products on the production line. This letter proposes a model to analyze this cost tradeoff against different sensing intervals. It further highlights the impact of energy harvesting sources on this cost relationship mapping a way toward improved production efficiency