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The availability of network softwarization and virtualization technology in the field of telecommunications has opened the door to a radical review of the applications, protocols, and deployment models. In this evolving framework, old assumptions and constraints specific to satellite communications must be carefully re-assessed. To this aim, we revisit the role of the performance enhancing proxy (PEP), replaced by a chain of custom virtual network functions properly enabled to optimize common web traffic performance over a backhaul dynamically enabled with a supplementary satellite link. The resulting virtual PEP (vPEP) is compliant with the breakthrough virtualization and slicing paradigms and can fruitfully exploit the advanced features of the most recent IETF technologies such as QUIC and MPTCP.

The pervasive use of technology in the urban environment requires evolved algorithms able to deliver messages across vehicular ad-hoc networks (VANETs). These networks could be exploited to run a vast plethora of applications, including critical ones such as emergency message distribution. The state-of-the-art broadcasting solutions are based on providing vehicles with different probabilities of forwarding the message in order to reduce message collisions and the number of hops to cover a certain area of interest. In this article, we examine a class of these propagation algorithms, discussing their model analysis and performance evaluation. Furthermore, we propose a possible algorithm’s extension introducing a dynamic setting of parameters according to the vehicular network’s conditions.

The ubiquity of mobile technology has opened the door to the new era of mobile sensing. Through this new paradigm, physical phenomena can be observed in a distributed way, crowd-sourcing the data measurement tasks to smartphones and/or other popular smart wearables. Mobile sensing and wireless communications can hence be employed to gather data and generate new information and services, benefiting our society. As a proof-of-concept, we have developed a mobile sensing platform able to pervasively collect environmental data. To improve the quality of collected data we have also created an application for pedestrian navigation that works both on smartphones (also using Augmented Reality) and on smartwatches, thus ensuring an appropriate exposition of the mobile device (and its sensors) when collecting data. Furthermore, our navigation app is able to provide users with personalized pedestrian routes that take into account environmental parameters and not only the route length. Finally, we have also devised a web service able to provide graphical visualization and historical evolution of sensed data.

We consider the scenario in which several TCP connections share the same access point (AP) and a congestion avoidance/control mechanism is adopted with the aim of assigning the available bandwidth to the clients with a certain fairness. When UDP traffic with real-time requirements is present, the problem becomes even more challenging. Very well-known congestion avoidance mechanisms are the Random Early Detection (RED) and the Explicit Congestion Notification (ECN). More recently, the Smart Access Point with Limited Advertised Window (SAP-LAW) has been proposed. Its main idea is that of computing the maximum TCP rate for each connection at the bottleneck, taking into account the UDP traffic to keep a low queue size combined with a reasonable bandwidth utilization. In this paper, we propose a new congestion control mechanism, namely, Smart-RED, inspired by SAP-LAW heuristic formula. We study its performance by using mean field models and compare the behaviours of ECN/RED, SAP-LAW, and Smart-RED under different scenarios. We show that while Smart-RED maintains some of the desirable properties of the SAP-LAW, it solves the problems it may have in case of bursty UDP traffic or TCP connections with very different needs of bandwidth.

Population aging is considered to be one of the most significant social transformations of the twenty-first century. In this paper, we evaluate the acceptability and usability of a system designed to silently monitor the activity and condition of older adults, with a particular focus on the elderly affected by cognitive decline. The system is composed of sensors that can be hidden in various wearable objects to collect data about a user and his/her surrounding environment and transmit them to a server for further elaboration. The aim is to improve safety and independence of older adults. We conducted a survey involving elderly people, their relatives and health practitioners to better assess their needs and provide them with a technology that is as little intrusive and visible as possible. The results of our survey are promising as the majority of the respondents expressed their willingness to use the proposed technology in their everyday lives.

Mobile Ad-Hoc Networks are currently experiencing a second youth in terms of research interest as well as providing benefits to our society. Clearly, this has been fostered by the wide range of applications that have become actually feasible thanks to the pervasive and increasing presence of smartphones, drones, sensors and other small devices with communication and sensing capability. Aiming to deploy solutions able to self-organize without the need for any infrastructure support, packet routing remains an open and critical research problem. Several routing solutions have been conceived to guarantee delivery and low overhead in this context. A promising approach, trying to limit the information needed and stored in the network, is represented by stateless solutions, a class of solutions not relying on topology state information. However, since they exploit local knowledge, the achieved performance in terms of packet delivery and latency is not always up to expectations. To this aim, we propose a dynamic routing protocol based on a tabu search approach, relying on local network knowledge and in-packet short-term memory to alleviate the local minima problem. A through experimental assessment is conducted, measuring protocol performance under different configurations and profiles, evidencing its benefits.

Simulations for network implementations are an essential component for developing newer and better network solutions and protocols, especially when considering complex scenarios. For instance, networks composed of flying objects coordinating through multi-hop communication represent a foreseeable scenario in our society. The need for analyzing new and tailored solutions for this visionary context passes through the creation of specific tools. To this aim, we present here a novel discrete event simulator deployed to test Flying Ad-Hoc Networks (FANETs) and, in particular, their routing algorithms. In our simulator we have also implemented two different position-based routing protocols for FANETs; their implementation and results are discussed as well.

Cloud-based interactive multimedia applications such as virtual games and video streaming are gaining high popularity. However, giving the high bandwidth consumption, the remote execution can negatively impact the quality of the multimedia traffic. In such a realm, data travel different communication networks from the cloud to the final users crossing the last meters the home's access point (AP). In such a scenario, the quality-of-service (QoS) support is a challenging task, particularly in the home network environment, with heterogeneous applications simultaneously running and consuming the available bandwidth. To address this issue, we propose ReiLeCS, a Reinforcement Learning-based Controller and Scheduler for interactive multimedia traffic in Home Area Networks (HAN). Through reinforcement learning and the maximization of a reward function, it enables the AP to schedule the arriving multimedia traffic from the cloud according to their required QoS. Simulation results using real multimedia traffic conditions demonstrate that ReiLeCS achieves better performances compared with existing packet scheduling policies.

This paper illustrates a possible solution to monitor humidity and temperature in indoor scenarios where it is crucial to maintain their values between predefined thresholds (e.g., museums). The system architecture is composed of wireless sensors, a gateway also including a wireless receiver and a Raspberry PI, a cloud database and a user interface. We illustrate how our system can be implemented following a frugal innovation approach, using non expensive wireless sensors and weather stations to create a cloud IoT real-time infrastructure.

Wearable technology is no longer science fiction. Thanks to the growing capability in the production chain to miniaturize complex electronics, a wide variety of gadgets that can be worn or included in dresses and accessories have emerged. These smart gadgets can collect data about the physical condition of the user and/or the environment providing the basis for innovative and valuable services. The main goal of this paper is to assess this context through field experiments undertaken in a testbed comprised of sensing hardware deployed on open source boards such as Arduino. Moreover, coupled with the sensing tier, we propose a proof-of-concept deployment architecture enabling a wide range of wearable sensors to collect and transmit data to a logically centralized unit.

Immersive technology is expected to become a key player in the next wave of consumer electronics with potential applications spanning a wide variety of sectors. Yet, there are a number of technological hurdles which need to be addressed. Without speed and computation capability, interactivity cannot be ensured. More than often the constrained nature of the mobile device demands is complemented by cloud ones through the use of cloud offloading techniques. With cloud offloading, battery consumption and processing performance problems are translated into sensor data selection and network latency problems. In this context, we focus our study on some functional building blocks that can be used in conjunction and deployed in a 5G virtualized architecture to alleviate bandwidth and latency requirements of immersive application scenarios. To this end, we have created an experimental scenario exploiting real data to test our combined solution based on the field of view cut and optimized transport protocols, discussing the tradeoffs that emerge.

The use of Procedural Content Generation techniques in the production of Video Games has seen a large diffusion in these last years. Regarding the procedural generation of Computer Graphics content, several works have been proposed about the automatic construction of complex models and environments, or about the instancing of several copies of a reference model, each with peculiar differences to introduce variety. However, very few works have proposed techniques for the procedural production of complex materials to be assigned to these generated models. In this paper, we present a method for the automatic generation of realistic layered materials based on the application of a Genetic Algorithm. We show that, with the proposed approach, is possible to generate several instances of a target material (e.g., a car paint, or a rusty metal), maintaining a desired level of closeness to the overall characteristics of the simulated interaction between the light and the surface, but introducing also a controlled amount of differences in the final reproduction of the perceived appearance.

Air quality and the presence of tiny particular matter are crucial factors in human health, especially when considering urban scenarios. In this context, smart mobility coupled with low-cost sensors can create a distributed and sustainable platform for social sensing able to provide pervasive data to citizens and public administrations. Sustainable and eco-aware decisions can then be supported by empirical evidence, resulting in an improved life and city administration. In this paper, we present ArduECO, a simple Arduino-based wireless device able of collecting air quality data. Without loss of generality, we have designed our device as a box that can be installed on a bike; in this way, beyond private bikes, municipalities could exploit their bike sharing fleets as pervasive sensing systems.

Automated Guided Vehicles (AGVs) are increasingly being employed in logistics to carry out tiring and repetitive tasks inside large industrial buildings. In these settings, AGVs perform more efficiently than human workers in that they exhibit no signs of fatigue, their movements can be tracked automatically and their path can be timed to feed/collect objects in a quasi-predictable time frame and to even perform some object manipulations/refinement during transportation. In this article, we present a simulation analysis assessing the feasibility of commodity WiFi for operations control in an autonomous production site. In this context, AGVs and infrastructure endpoints are involved in periodic data exchange, the later gathering and acting upon AGV health data in order to ensure the systems operations continuity. To this end, we have setup a realistic simulation scenario mimicking the sites’ operational environment discussing some trade-offs that emerge.

Even if the World Wide Web is one of the main content and service providers, unfortunately, these contents and services are not really available for everyone. People affected by impairments often have difficulties in navigating Web pages for a wide range of reasons. In this paper, we focus on people affected by dyslexia. These users experience difficulties in reading acquisition, despite normal intelligence and adequate access to conventional instruction. For this reason, we have created Help me read!, a Chrome extension that allows to change many features of a Web page. Furthermore, it allows to isolate and enlarge one word at a time. This feature is crucial as it allows people with dyslexia to focus on each single word, thus overcoming one of their main difficulties.

Proper waste sorting is crucial for both economic and environmental reasons. Yet, its effectiveness can be strongly limited when citizens do not know how to correctly separate waste, sometimes even due to different regulations depending on their municipality. We have hence devoted our efforts to the creation of a serious game able to teach people of all ages how to match the various trash cans with the corresponding type of waste. Although we have considered the city of Padua, Italy, as a case study, our application can be easily adapted to different waste sorting regulations.

The fruition of multimedia contents has been revolutionized by the spread of broadband technology. Furthermore, the advent of the cloud is now moving the computational load, once prerogative of domestic devices, to remote servers. This is bringing achievements that were unthinkable only few years ago, like the provisioning of new multimedia services through the Internet. To guarantee a proper user experience, a low E2E latency and a high bandwidth are both essential. Unfortunately, this is difficult to accomplish in a shared and best-effort network like the Internet. We need to focus on the study and analysis of modern network protocols to identify viable solutions for a suitable user experience. This is especially the case of QUIC, a recent transport protocol able to reduce significantly some issues mentioned above. Our aim is to explore QUIC and its integration into a Smart Access Point, enabling a better management of heterogeneous co-existing media flows.

Drones are more and more important in emergency response scenarios, where they can be equipped with wireless access points and deployed to configure a recovery ad-hoc flying network, e.g., to interconnect users positioned in a disaster area. Communication between users is allowed by means of multi-hop paths including one or more relay drones. An interesting optimization problem asks for determining the position of a minimum number of drones in order to guarantee that all the required communication paths can be established. Wireless channels are used and interference plays an important role: we propose an interference model and we embed it in a Mixed Integer Linear Programming formulation. Preliminary computational results are presented, showing the proposed model is able to solve instances of medium size in order of minutes.

International audience; ICT components of vehicular and transportation systems have a crucial role in ensuring passengers’ safety, particularly in the scenario of vehicular networks. Hence, security concerns should not be overlooked, since a malicious vehicle might inject false information into the intervehicle wireless links, leading to life and money losses. This is even more critical when considering applications specifically aimed at improving people’s safety, such as accident warning systems. To assess the scenario of such type of applications in a vehicular network, we have performed a thorough evaluation of accident warning systems under a position cheating attack. As one of the main contributions of this paper, we determine the impact of a different number of malicious vehicles on delaying the alert warning messages. In particular, we study the impact of the position of malicious vehicles on delaying alert messages. We identify the most effective strategies that could be used by malicious vehicles in order to maximize the delay of the alert message, and thus strengthen the impact of the attacker. Finally, we pinpoint that even with a small number of malicious vehicles, the positioning cheating attack can significantly increase the delay of the alert message when compared to a scenario without attack.

The actual advent of autonomous vehicles and the general improvement of traffic safety pass through quick and reliable message dissemination in a certain Area of Interest (AoI). Message dissemination among the vehicles composing an Internet of Vehicles (IoV) is of paramount importance and has to make use of fast and efficient multi-hop message forwarding to broadcast information. While most of existing works focus only on simple car platooning scenarios (e.g., a highway), we discuss here a fast multi-hop broadcast protocol able to quickly and reliably propagate an alert message even in general 2D (and 3D) topology scenarios.

The advent of broadband technology has revolutionized the fruition of multimedia contents. Moreover, the cloud is now moving the computational load from domestic devices to remote servers, enabling the provisioning of new multimedia services through the Internet. To provide a proper user experience, a low E2E latency and a high bandwidth are both required. Unfortunately, this is difficult to achieve in a shared network like the Internet. My PhD project focuses on the study and analysis of modern network protocols to identify viable solutions for a suitable user experience.

The technological evolution in the mobile sector has experienced an exponential growth in the last years. The number of functionalities has grown, and of course the way we use these devices has changed. Starting with calls and messages, introducing cameras, implementing Internet connectivity, and finally introducing the sensor technology, we arrive to today's smartphones. Following this trend, a popular application as gaming has extended its domain from home computers and consoles to the mobile realm. While there are many developers working on modern game genres, we devised a mobile game that join the rediscovery of ancient board games with the pleasure to play on a smart device. Through the development of the digital version of a game that was played centuries ago, we have created a very attractive tool able to raise the interest of children toward ancient history. We hence discuss here our attempt to digitally rediscover and enhance an ancient board game called "Fox and Geese"

Augmented and virtual reality technology are expected to become key technological players in the next wave of consumer electronics with potential applications spanning a wide variety of economic sectors. Yet, there are a number of technological hurdles which need to be addressed. Without speed and computation capability interactivity cannot work. More than often the constrained nature of the mobile device demands are complemented by cloud ones through the use of cloud offloading techniques. With cloud offloading, battery consumption and processing performance problems are translated into sensor data selection and network latency problems. In this context, we focus our study on a network function which could be deployed in a 5G virtualized architecture to alleviate bandwidth requirements of immersive application scenarios. To this end, we rely on a real dataset, providing user-centric metadata on several 4k, 360-degree videos. Different computational methods are proposed and contrasted, evidencing the goodput of the approaches.

Recent market trends in self-driving technology have revived the attention on vehicular networks, posing a demand for intelligent solutions supporting the proliferation of many useful applications. Inter-vehicular communication presents an opportunity, capable of providing the basis for localized, timely, collective intelligence. In this context, critical safety applications are particularly challenging, urging for quick multi-hop message propagation schemes within an area of interest. The anycast communication model embodied by safety applications and the shared broadcast medium demand for intelligent message propagation schemes minimizing latency. To this end, the state of the art approach is based on having different contention windows among vehicles so as to probabilistically select specific ones as forwarders in order to reduce the number of hops and transmissions needed to propagate the message. However, this solution has been mainly studied empirically. In this article, we present and discuss an analytical model, shedding light on the expected behavior and performance of such approach, along with a validation analysis conducted through the well known simulator NS-2.

We present the design and implementation aspects of a virtualized Performance Enhancing Proxy (vPEP), in a 5G compliant architecture involving the satellite as an alternate, additional backhaul link. The deployment of hybrid terrestrial-satellite configurations is realized through the vPEP agent, meant as a chain of Virtual Network Functions (VNFs), enhancing protocol performance and/or bringing value-added services in the end-to-end path. To this end, we discuss a possible integration approach of the satellite link into the 5G service-based architecture, outlining key functional components. In addition, we present a preliminary evaluation study employing a vPEP embodying the QUIC protocol in a possible web-browsing, 5G optimized slice.

We discuss MDTN: a delay tolerant application platform built on top of the Public Transportation System (PTS) and able to provide service access while exploiting opportunistic connectivity. Our solution adopts a carrier-based approach where buses act as data collectors for user requests requiring Internet access. Simulations based on real maps and PTS routes with state-of-the-art routing protocols demonstrate that MDTN represents a viable solution for elastic nonreal-time service delivery. Nevertheless, performance indexes of the considered routing policies show that there is no golden rule for optimal performance and a tailored routing strategy is required for each specific case.

In this paper, we propose GeoSaW, a delay-tolerant routing protocol for Airborne Networks in Search and Rescue scenarios. The protocol exploits the geographical information of UAVs to make appropriate message forwarding decisions. More precisely, the information about the future UAV&rsquo, s motion path is exploited to select the best UAV carrying the message towards the destination. Simulation results show that the proposed solution outperforms the classic DTN routing protocols in terms of several performance metrics.

Vehicular networks are receiving more and more attention from researchers and practitioners. In this context, it is particularly interesting to study realistic scenarios where vehicles are connected among themselves, or with other nodes. Think, for instance, of cooperating interconnecting objects forming an Internet of Vehicles (IoV) to collectively decide on maneuvers. Such connected autonomous vehicles would certainly require fast but also reliable group communications. Broadcast in wireless networks would be useful in this scenario if a tradeoff between reliable message delivery and low overhead can be solved. To this aim, we evaluate the performance of probabilistic flooding schemes and propose a heuristic-based solution that seems promising in fitting the IoV's needs.

Unmanned aerial vehicles (UAV), or commonly referred to as Drones, have captured our imagination bringing new and challenging service provisioning schemes into the networking scenario. We might indeed be reaching the day where communication-enabled drones might be employed in synergy with deployed public networks offering alternate service access means. In this context, we contribute with quantitative analysis of classic routing algorithms in a 3D mobile environment, shedding some light on their performance tradeoffs.

This work aims to design and develop a web application for reading and attentional evaluation in schooling children using a standardized tests battery. The application allows the automatic and immediate calculation of child's scores by inserting times and errors committed by the subject. The obtained scores are needed to establish whether the participant's performance is in deficit or not (i.e., Z-score).

Scalable routing for wireless communication systems is a compelling and challenging task. To this aim, routing algorithms exploiting geographic information have been proposed. These algorithms refer to nodes by their location, rather than their address, and use those coordinates to route greedily towards a destination. With the advent of unmanned airborne vehicle (UAV) technology, a lot of research effort has been devoted to extend position-based packet routing proposals to three dimensional environments. In this context, Flying Ad-hoc Networks (FANETs), comprised of autonomous flying vehicles, pose several issues. This work focuses on the state-of-the-art, stateless geographic packet routing protocols conceived or adapted for three-dimensional network scenarios. Proposals are evaluated over a common scenario through a comprehensive comparative analysis.

In recent years we have seen a great proliferation of smart vehicles, ranging from cars to little drones (both terrestrial and aerial), all endowed with sensors and communication capabilities. It is hence easy to foresee a future with even more smart and connected vehicles moving around, occupying space and creating an Internet of Vehicles (IoV). In this IoV, a multitude of nodes (both static and mobile) will generate a continuous multihop flow of local information to support local smart environment applications. Therefore, one interesting environment for the IoV would be in the form of 3-D mobile ad-hoc networks (MANETs). Unfortunately, MANET routing protocols have generally been designed and analyzed keeping in mind a 2-D scenario; there is no guarantee on how they would support a 3-D topology of the IoV. To this end, we have considered routing protocols deemed as the state-of-the-art for classic MANETs and tested them over 3-D topologies to evaluate their assets and technical challenges.