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2022
Falko Dressler, Carla Fabiana Chiasserini, Frank H. P. Fitzek, Holger Karl, Renato Lo Cigno, Antonio Capone, Claudio Casetti, Francesco Malandrino, Vincenzo Mancuso, Florian Klingler, Gianluca Rizzo
IEEE Network, 2022, vol. 36, no. 3, pp. 24–31
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Résumé:
As we move from 5G to 6G, edge computing is one of the concepts that needs revisiting. Its core idea is still intriguing: Instead of sending all data and tasks from an end user's device to the cloud, possibly covering thousands of kilometers and introducing delays lower-bounded by propagation speed, edge servers deployed in close proximity to the user (e.g., at some base station) serve as proxy for the cloud. This is particularly interesting for upcoming machine-learning-based intelligent services, which require substantial computational and networking performance for continuous model training. However, this promising idea is hampered by the limited number of such edge servers. In this article, we discuss a way forward, namely the V-Edge concept. V-Edge helps bridge the gap between cloud, edge, and fog by virtualizing all available resources including the end users' devices and making these resources widely available. Thus, V-Edge acts as an enabler for novel microservices as well as cooperative computing solutions in next-generation networks. We introduce the general V-Edge architecture, and we characterize some of the key research challenges to overcome in order to enable wide-spread and intelligent edge services.
2021
Gianluca Rizzo, Noelia Perez Palma, Marco Ajmone Marsan, Vincenzo Mancuso
IEEE transactions on mobile computing, To be published
Floating Content (FC) is a paradigm for localized infrastructure-less content dissemination, that aims at sharing information among nodes within a restricted geographical area by relying only on opportunistic content exchanges. FC provides the basis for the probabilistic spatial storage of shared information in a completely decentralized fashion, usually without support from dedicated infrastructure. One of the key open issues in FC is the characterization of its performance limits as functions of the system parameters, accounting for its reliance on volatile wireless exchanges and on limited user resources. This paper takes a first step towards tackling this issue, by elaborating a model for the storage capacity of FC, i.e., for the maximum amount of information that can be stored through the FC paradigm. The storage capacity of FC, and of similar probabilistic content dissemination systems, is evaluated with a powerful information theoretical approach, based on a mean field model of opportunistic information exchange. In addition, an extremely simple explicit approximate expression for storage capacity is derived. The numerical results generated by our analytical models are compared to the predictions of realistic simulations under different setups, proving the accuracy of our analytical approaches, and characterizing the properties of the FC storage capacity.
2020
Gianluca Rizzo, Sasko Ristov, Thomas Fahringer, Marjan Gusev, Matija Dzanko, Ivana Bilic, Christian Esposito, Torsten Braun
Dans Hutchison, David, Rak, Jacek, Guide to disaster-resilient communication networks (Pp. 271-298). 2020, Cham : Springer
The focus of this chapter is on communication (and partially, computing) solutions which allow satisfying demands from the immediate aftermath of a disaster until full restoration of pre-disaster communication infrastructure and services. As traffic demand might differ substantially from the one in the pre-disaster scenario, due to the specific needs of post-disaster scenarios, it appears evident that a simple restoration of existing infrastructure and services might not be sufficient to satisfy it, and that specific solutions are required. This chapter reviews the most relevant post-disaster scenarios, outlining a set of reference use cases and their communication requirements. Then, it presents an overview of the state of the art for emergency and post-disaster communications. Finally, it focuses on a set of specific solutions of special relevance for disaster scenarios, outlining the main research challenges which are open to date.
Christian Esposito, Zhongliang Zhao, Gianluca Rizzo, Florin Pop, Elena Apostol, Catalin Leordeanu, Stefan Preda
Dans Hutchison, David, Rak, Jacek, Guide to disaster-resilient communication networks (Pp. 605-628). 2020, Cham : Springer
Current networks should provide disaster-resilience by coping with the possible failures and misbehaviours caused by massive natural or man-made disasters. This is necessary to keep a suitable level of Quality of Service after a disaster and to support the possible evacuation, rescue, assessment, and rescue operations within the affected area. Multiple possible methods and solutions can be put in place in a proactive and/or reactive manner to offer the required resilience degree. Among them, a proper routing algorithm can contribute to circumventing network elements damaged by the disaster or applying for spatial/temporal redundancy to guarantee effective communications. This chapter aims at presenting the main routing solutions to offer disaster-resilience communications, along with some related methods.
Antonio Jara, Luc Dufour, Gianluca Rizzo, Marcin Piotr Pawlowski, Dominique Genoud, Alexandre Cotting, Yann Bocchi, François Chabbey
Dans Management Association, Information Resources, Securing the internet of things: concepts, methodologies, tools, and applications (Pp. 630-654). 2020, Hershey : IGI Global
Microgrids present the challenge to reach a proper balance between local production and consumption, in order to reduce the usage of energy from external sources. This work presents a data-intensive solution to predict the energy behaviors. Thereby, control actions can be carried out such as decrease heating systems levels and switch of low-priority devices. For this purpose, this work has deployed an Advanced Metering Infrastructure (AMI) based on the Internet of Things (IoT) in the Techno-Pole testbed. This deployment provides the data from energy-related parameters such as load curves of the overall building through Non-Intrusive Load Monitoring (NILM), a wireless network of IoT-based smart meters to measure and control appliances, and finally the generated power curve by 2000 square meters of photovoltaic panels. The prediction model proposed is based on recognition of electrical signatures. These electrical signatures have been used to detect complex usage patterns. The modelled patterns have allowed to identify the work day of the week, and predict the load and generation curves for 15 minutes with accuracy over the 90%. This short-term prediction allows one to carry out the proper actions in order to balance the microgrid status (i.e., get a proper balance between production and consumption with respect to worked requirements).
2019
Christian Esposito, Zhongliang Zhao, Ramon Alcarria, Gianluca Rizzo
Dans Coleri Ergen, Sinem, Palattella, Maria Rita, Scanzio, Stefano, Ad-Hoc, Mobile, and Wireless Networks : 18th International Conference on Ad-Hoc Networks and Wireless, ADHOC-NOW 2019, Luxembourg, Luxembourg, October 1–3, 2019, Proceedings (pp. 18-31). 2019, Cham : Springer
The availability of effective communications in post-disaster scenarios is key to implement emergency networks that enable the sharing of critical information and support the coordination of the emergency response. To deliver those levels of QoS suitable to these applications, it is vital to exploit the multiple communication opportunities made available by the progressive deployment of the 5G and Smart City paradigms, ranging from ad-hoc networks among smartphones and surviving IoT devices, to cellular networks but also drone-based and vehicle-based wireless access networks. Therefore, the user device should be able to opportunistically select the most convenient among them to satisfy the demands for QoS imposed by the applications and also minimize the power consumption. The driving idea of this paper is to leverage non-cooperative game theory to design such an opportunistic user association strategy in a post-disaster scenario using UAV ad-hoc networks. The adaptive game-theoretic scheme allows increasing of the QoS of the communication means by lowering the loss rate and also keeps moderate the energy consumption.
Flavien Bonvin, Gaetano Manzo, Christian Esposito, Braun Torsten, Gianluca Rizzo
Dans Coleri Ergen, Sinem, Palattella, Maria Rita, Scanzio, Stefano, Ad-Hoc, mobile, and wireless networks : 18th International Conference on Ad-Hoc Networks and Wireless, ADHOC-NOW 2019, Luxembourg, Luxembourg, October 1–3, 2019, Proceedings (9 p.). 2019, Cham : Springer
In the immediate aftermath of nature-based disasters such as earthquakes, fires, or floods, have a clear vision of the situation and the population involved is of main priority for rescue operations—it is a matter of life and death. But these disaster events may cause malfunctions in communication services making the exchange information impossible—the experienced delay sending a message in an overcrowded area is a shred of evidence. In this demo, we introduce Floater, a mobile awareness-based communication application for the immediate aftermath of a disaster, when ad hoc infrastructure support has not been deployed yet. Floater enables communications between peers in a common area without requiring the support of a cellular network. The application is developed for Android and it does not require an account or an Internet connection. Floater exploits local knowledge and constraints opportunistic replication (peer to peer) of information to build a global view of the involved area efficiently. The app is the first to implement Floating Content, an infrastructure-less communication paradigm based on opportunistic replication of a piece of content in a geographically constrained location and for a limited amount of time. The demo illustrates the feasibility and the main functionalities of Floater and presents disaster assistance use cases for supporting rescue operations.
Gaetano Manzo, Marco Ajmone Marsan, Gianluca Rizzo
Ad hoc networks, 15 May 2019, vol. 88, pp. 65-80
Among the many proposed opportunistic content sharing schemes, Floating Content (FC) is of special interest for the vehicular environment, not only for cellular traffic offloading, but also as a natural communication paradigm for location-based context-aware vehicular applications. Previously published results on the performance of vehicular FC have mostly focused on the conditions under which content persists over time in a given region of space, without addressing other important aspects of vehicular FC performance, such as the effectiveness with which content is replicated and made available, and the system conditions that enable good FC performance. This work presents a first analytical model of FC performance in vehicular networks in urban settings. It is based on a new synthetic mobility model (called District Mobility Model - DMM), and it does not require a detailed knowledge of the road grid geometry. We validate our model extensively, by comparison against numerical simulations based on real-world traces, and we prove our model accuracy under a variety of mobility patterns and traffic conditions. Our analytical and simulation results provide evidence of the effectiveness of theFC paradigm in realistic urban settings over a wide range of traffic conditions.
2018
Gaetano Manzo, Sebastian Otálora, Marco Ajmon Marsan, Gianluca Rizzo
ACM SIGMETRICS performance evaluation review, December 2018, vol. 46, no. 3
Floating Content (FC) is a communication paradigm for the local dissemination of contextualized information through D2D connectivity, in a way which minimizes the use of resources while achieving some specified performance target. Existing approaches to FC dimensioning are based on unrealistic system assumptions that make them, highly inaccurate and overly conservative when applied in realistic settings. In this paper, we present a first step towards the development of a cognitive approach to efficient dynamic management of FC. We propose a deep learning strategy for FC dimensioning, which exploits a Convolutional Neural Network (CNN) to efficiently modulate over time the resources employed by FC in a QoS-aware manner. Numerical evaluations show that our approach achieves a maximum rejection rate of 3%, and resource savings of 37.5% with respect to the benchmark strategy.
Gianluca Rizzo, Vincenzo Mancuso, Shahzad Ali, Marco Ajmone Marsan
Ad Hoc networks, September 2018, vol. 78, pp. 54-72
In this paper we study an opportunistic geographically constrained information sharing paradigm known under the name Floating Content (FC), considering two different mobility models that describe the behav- ior of pedestrians. We assume that users carrying their smartphones walk from one location to another and then stop for a while. Information transfers take place in the periods when users pause between movements. We develop analytical models to compute the performance metrics that characterize FC in this case and we validate analytical results with data collected during an experiment performed in a uni- versity campus. The comparison proves the accuracy of our analytical models. Moreover, results unveil the key relevance for FC performance of group dynamics in user movements.
Borja Bordel, Ramón Alcaria, Gianluca Rizzo, Antonio Jara
Dans Guarda, Teresa, Rocha, Álvaro, Proceedings of the International Conference on Information Technology & Systems (ICITS 2018) (Pp. 319-329). 2018, Cham : Springer
Monitoring the road network status of an entire country in a visual way (as traditionally) is very hard, so different mechanisms to do it in an automatic manner have been investigated. In particular, nomadic pervasive sensing platforms based on VANETs have been recently deployed. However, the level of road damage is a relative variable, and it is necessary to predict the particular impact of the same in each case, in order to prioritize the conditioning works. Therefore, in this paper a predictive model for forecasting the accident rate in mountain roads, considering the measures previously obtained through a nomadic sensing environment (and through the weather office) is defined. The model considers the type of road under study as well as different analysis scales to perform the calculations. The model is based on Taylor’s series and multivariate functions. Real data related to Valais (Switzerland) road network is employed to construct and validate the proposed model.
2017
Audrey Dupont, Yann Bocchi, Gianluca Rizzo
Innovative mobile and internet services in ubiquitous computing : proceedings of the 11th International Conference on Innovative Mobile and Internet Services in Ubiquitous Computing (IMIS-2017) (pp. 884-893). 2017, Cham, Springer : Cham, Springer
The Smart City paradigm is progressively shaping the way we inter-act with other citizens, with institutions, as well as the way in which all kind of resources are managed in an urban setting. However, the high cost of dedicated sensing, computing and communication infrastructure, represents one of the main obstacles to the adoption of the Smart City paradigm in small cities and large, dis-tributed districts, where resides the vast majority of the world population. In this paper we present a first implementation of a platform for nomadic sensing, which exploits the moving infrastructure of a city in order to implement the sensing, computing and communication functionalities required by smart city services, in a cost-effective way. This paper describes the architecture of the NOSE system, and the main lessons learned during the first steps of its implementation, deploy-ment, and experimental validation. In particular, we show that the main technical challenges are due to the lack of devices conceived for reliable mobile operation (sensing, computing) and to the difficulty in achieving high levels of accuracy in measurements while moving.
Gianluca Rizzo, Helmut Neukirchen
International Conference on Innovative Mobile and Internet Services in Ubiquitous Computing : IMIS 2017: Innovative Mobile and Internet Services in Ubiquitous Computing (pp. 894-903). 2017, Cham : Springer
Floating Content (FC) is an infrastructure-less communication paradigm based on opportunistic replication of a piece of content in a geographically constrained location and for a limited amount of time. The fact that it does not rely on any infrastructure makes it appealing for all those settings where infrastructure is not available or malfunctioning. In this paper we analyze its feasibility in the aftermath of a disaster, as a communication service in support of applications for rescue coordination and situational awareness. We analyze the possible scenarios of disaster, with a special focus on the local context (Iceland in our case), and on a subset of disasters which are of economic and social interests. We characterize the available communication network, its structure, and we individuate some criticalities which could play a key role in case of disaster. Specifically, we consider two services, related to two disaster scenarios. A first one is a form of situation awareness, without the support of fixed communication infrastructure. A second service is a form of infrastructure-less social driving application. The exchange of information between vehicles in the vicinity of a region interested by a disaster, enabled by such app, could help mitigate the impact of disasters and hazardous conditions on vehicle traffic. For both services, we describe a possible implementation using Floating Content. Finally, for these scenarios, we identify some research issues which stand in the way of a realistic, practical implementation based on FC.
2016
Alex Carmine Olivieri, Gianluca Rizzo, Yann Bocchi
Pervasive computing: next generation platforms for intelligent data collection (pp. 97-128). 2016, Amsterdam : Elsevier
The advent of the Internet of Things (IoT) opens a wide spectrum of interesting opportunities for the creation of novel scenarios. By incorporating communication devices such as sensors and actuators, into mainstream technologies, IoT enables a whole set of new services in almost any domain to be provided, from building automation to Smart City, E-Health, and assistive technologies, to name just a few. Nevertheless, the integration of different protocols and technologies remain to date one of the main challenges in IoT. The proposed solutions have evolved following the heterogeneity increment of the technologies employed for complex scenarios, passing from ad hoc solutions on a per-connection basis (N-to-N), to solutions that use frameworks as middleware (N-to-1). N-to-1 solutions that have shown interesting features use frameworks modeled on the Publish/Subscribe (P/S) design pattern. This type of framework provides facilities to manage the exchange of communications in the presence of a large number of heterogeneous communication technologies. However, how to efficiently interface those technologies with a common framework still remains an open issue. In this work we propose to surround a P/S framework with a layer that allows us to easily interface the various communication technologies with the framework. We describe how to model this layer, and we show how to implement simple adaptors that can be used to interface a technology with the selected P/S framework. We show how our approach makes the integration of heterogeneous technologies easier and how it enables scenarios’ reconfigurations even at run time. By using such an approach, designers can focus on the business logic of the scenario rather than on the low-level technological details of the integration. We inform the reader about the lessons learned throughout the realization of the proposed approach and about the tasks that we found more challenging in making the final system; by doing so we intend to inculcate in the reader some questions that could lead to some interesting future research in order to address some challenges that remain open.
Gianluca Rizzo, et al.
Peer-to-peer networking and applications, Vol. 9, no. 38, pp. 1-20
The impact of the ICT sector in worldwide power consumption is an increasing concern, motivating the research community to devote an important effort to define novel energy efficient networking solutions. Despite file distribution is responsible for a major portion of the current Internet traffic, little effort has been dedicated to address the issue of its energy efficiency so far. Most of the previous literature focuses on optimizing the download time of file distribution schemes (e.g. centralized server-based or distributed peer-to-peer solutions) while it is yet unclear how to optimize file distribution schemes from the point of view of energy consumed. In this paper, we present a general modelling framework to analyze the energy consumption of file distribution systems. First, we show that the general problem of minimizing energy consumption in file distribution is NP-hard. Then, for restricted versions of the problem, we establish theoretical bounds to minimal energy consumption. Furthermore, we define a set of optimal algorithms for a variety of system settings, which exploit the service capabilities of hosts in a P2P fashion. We show that our schemes are capable of reducing at least 50 % of the energy consumed by traditional (yet largely used) centralized distribution schemes even when considering effects such as network congestion and heterogeneous access speed across nodes.
Gianluca Rizzo
IEEE Journal on selected areas in communications, March 2016, vol. 34, no. 3, pp. 510-527
The IoT paradigm holds the promise to revolutionize the way we live and work by means of a wealth of new services, based on seamless interactions between a large amount of heterogeneous devices. After decades of conceptual inception of the IoT, in recent years a large variety of communication technologies has gradually emerged, reflecting a large diversity of application domains and of communication requirements. Such heterogeneity and fragmentation of the connectivity landscape is currently hampering the full realization of the IoT vision, by posing several complex integration challenges. In this context, the advent of 5G cellular systems, with the availability of a connectivity technology, which is at once truly ubiquitous, reliable, scalable, and cost-efficient, is considered as a potentially key driver for the yet-to emerge global IoT. In the present paper, we analyze in detail the potential of 5G technologies for the IoT, by considering both the technological and standardization aspects. We review the present-day IoT connectivity landscape, as well as the main 5G enablers for the IoT. Last but not least, we illustrate the massive business shifts that a tight link between IoT and 5G may cause in the operator and vendors ecosystem.
2014
Gianluca Rizzo, Marco Marsan, Balaji Rengarajan
Computer Networks, February 2015, vol. 78, pp. 152–163
Sleep modes are widely accepted as an effective technique for energy-efficient networking: by adequately putting to sleep and waking up network resources according to traffic demands, a proportionality between energy consumption and network utilization can be approached, with important reductions in energy consumption. Previous studies have investigated and evaluated sleep modes for wireless access networks, computing variable percentages of energy savings. In this paper we characterize the maximum energy saving that can be achieved in a cellular wireless access network under a given performance constraint. In particular, our approach allows the derivation of realistic estimates of the energy-optimal density of base stations corresponding to a given user density, under a fixed performance constraint. Our results allow different sleep mode proposals to be measured against the maximum theoretically achievable improvement. We show, through numerical evaluation, the possible energy savings in today’s networks, and we further demonstrate that even with the development of highly energy-efficient hardware, a holistic approach incorporating system level techniques is essential to achieving maximum energy efficiency.
Gianluca Rizzo, Marco Ajmone Marsan, Christian Esposito
WiOpt 2022 Proceedings
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Internet of Things (IoT) devices often have batteries of limited capacity, which are not easily replaced or recharged. This implies very short device lifetimes, and calls for a very careful device configuration to achieve the optimal trade-off between performance and power consumption. SWIPT (Simultaneous Wireless Information and Power Transfer) deals with this problem by harvesting energy at IoT devices from the received RF signals. Studying the efficiency of SWIPT in dealing with the energy and data transfer demands of IoT nodes leads to a number of open issues. In this paper, we devise an analytical model based on stochastic geometry for a SWIPT radio access network with a dense population of IoT users. With our model, it is possible to accurately study the impact of the system parameters on the key system performance indicators, while accounting in a realistic manner for device performance, and for the statistics of time scheduling at base stations. This allows us to understand (not without some surprise) what are the most effective strategies to minimize energy consumption in a SWIPT network, and what is their potential for energy savings.
Nhat Nguyen, Duong Nguyen, Junae Kim, Gianluca Rizzo, Hung Nguyen
Proceedings of 2022 IEEE 23rd International Symposium on a World of Wireless, Mobile and Multimedia Networks (WoWMoM)
Coordinated multi-robot systems are an effective way to harvest data from sensor networks and to implement active perception strategies. However, achieving efficient coordination in a way which guarantees a target QoS while adapting dynamically to changes (in the environment, due to sensors’ mobility, and/or in the value of harvested data) is to date a key open issue. In this paper, we propose a novel decentralized Monte Carlo Tree Search algorithm (MCTS) which allows agents to optimize their own actions while achieving some form of coordination, in a changing environment. Its key underlying idea is to balance in an adaptive manner the exploration-exploitation trade-off to deal effectively with abrupt changes caused by the environment and random changes caused by other agents’ actions. Critically, outdated and irrelevant samples - an inherent and prevalent feature in all multi-agent MCTS-based algorithms - are filtered out by means of a sliding window mechanism. We show both theoretically and through simulations that our algorithm provides a log-factor (in terms of time steps) smaller regret than state-of-the-art decentralized multi-agent planning methods. We instantiate our approach on the problem of underwater data collection, showing on a set of different models for changes that our approach greatly outperforms the best available algorithms for that setting, both in terms of convergence speed and of global utility.
Mina Aghaei Dinani, Adrian Holzer, Hung Nguyen, Marco Ajmone Marsan, Gianluca Rizzo
Proceedings of 2022 IEEE Wireless Communications and Networking Conference (WCNC)
Christian Esposito, Gianluca Rizzo
Proceedings of the 2022 IEEE 19th Annual Consumer Communications & Networking Conference (CCNC)
Natural and man-made disasters have often consequences on service availability in a wireless access network, provoking a progressively degraded performance or even the lack of connectivity. However, given the growing importance of situation awareness, telehealth, and advanced rescue teams coordination services for the affected population, it is key to restore these services in a timely fashion, while guaranteeing the required QoS levels. To this end, UAV-mounted base stations have been recently proposed as a key instrument to achieve this goal. Nonetheless, this gives rise to the key issue of how to deploy them in a resource efficient manner, in a post-disaster context typically characterized by lack of infrastructure support and of power supply. In this work, we tackle the issue of how to jointly optimize drones deployment and user association in a QOS aware manner to efficiently cater for coverage holes and QoS degradation in a cellular network after a disaster. We formulate a network optimization problem, and we provide a two-step genetic algorithm which iteratively tunes UAV position, base station transmit power and user association in order to minimize the number of employed drones. Initial results on a realistic measurement based scenario show that our approach is able to effectively minimize the number of deployed drones while achieving a target minimum QoS.
Proceedings of the 2021 IEEE Wireless Communications and Networking Conference
Gossip Learning (GL) is a peer-to-peer machine learning protocol based on direct, opportunistic exchange of models among nodes via wireless D2D communications, and on collaborative model training, which has recently proven to scale efficiently to large numbers of nodes, and to offer better privacy guarantees than traditional centralized learning architectures. Existing approaches to GL are however limited to scenarios in which nodes are static, or in which the node connectivity graph is fully connected, and they are fragile to node churn as well as to any change in network configuration. To overcome this limitation, we present a new decentralized architecture for GL suitable for setups with dynamic nodes, which benefits from node mobility instead of being hampered by it. In our approach, nodes improve their personalized model instance by sharing it with neighbors, and by weighting neighbors' contributions according to an estimate of their marginal utility. We apply our GL algorithm to short-term vehicular trajectory estimation in realistic urban scenarios. We propose a new strategy for the estimation of the neighbors' instances marginal utility, which yields satisfactory trajectory estimation accuracy for nodes with long enough sojourn times.
Proceedings of the 2020 IEEE Vehicular Networking Conference (VNC)
Gossip Learning (GL) is a fully decentralized machine learning paradigm with the potential to enable highly scalability and to preserve user privacy. The majority of existing results however consider scenarios in which either each node communicates with all other nodes, or in which the connectivity graph is static, and they are therefore inapplicable in dynamic setups such as in VANETs. This work is a first attempt at designing and assessing GL schemes suited for scenarios with moving nodes with the application of predicting the trajectory of moving cars.
Proceedings of the 21st IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks (WoWMoM)
Floating Content (FC) is a paradigmatic example of opportunistic infrastructure-less content sharing system where information is spread upon mobile node encounters within an area which is called the replication zone. FC allows the probabilistic spatial storage of information, even in the case of unreliable communications, with no support from dedicated servers. Given the large amount of communication and storage resources typically required to guarantee content persistence despite node mobility, a major open issue for the practical viability of FC and of similar distributed storage systems is the characterization of their storage capacity, i.e., of the maximum amount of information which can be stored for a given set of system parameters. In this paper, we propose a simple yet powerful information theoretical model of the storage capacity of probabilistic distributed storage systems such as FC, based on a mean field model of opportunistic information exchange. We evaluate numerically our results, and validate the model by means of realistic simulations, showing the accuracy of our mean field approach and characterizing the properties of the FC storage capacity versus the main system parameters.
Gaetano Manzo, Eirini Kalogeiton, Antonio Di Maio, Torsten Braun, Maria Rita Palattella, Ion Turcanu, Ridha Soua, Gianluca Rizzo
Proceedings of the 21st International Symposium on a World of Wireless, Mobile and Multimedia Networks (IEEE WoWMoM 2020)
Although many target applications in VANETs are information-centric, the performance of Named Data Networking (NDN) in vehicular ad-hoc networks is severely hampered by persistent network partitioning, typical of many vehicular scenarios. Existing approaches try to address this issue by relying on opportunistic communications. However, they leave open the crucial issue of how to guarantee content persistence and tight QoS levels while optimizing the resource utilization in the vehicular environment. In this work we propose DeepNDN, a communication scheme based on the joint application of NDN and of probabilistic spatial content caching, which enables content retrieval in fragmented and dynamic network topologies with tight delay constraints. We present a data-based approach to DeepNDN management, based on locally modulating content replication and delivery in order to achieve a target hit ratio in a resource-efficient manner. Our management algorithm employs a Convolutional Neural Network (CNN) architecture for effectively capturing the complex relations between spatio-temporal patterns of mobility and content requests and DeepNDN performance. Its numerical assessment in realistic, measurement-based scenarios suggest that our management approach achieves its target set goals while outperforming a set of reference schemes.
Gaetano Manzon, Flavien Bonvin, Christian Esposito, Torsten Braun, Gianluca Rizzo
Proceedings of the 35th Annual ACM Symposium on Applied Computing
The majority of communication solutions for post-disaster areas rely on cellular infrastructure support. But disasters such as fires, floods, earthquakes, can disrupt communication network making its services unavailable. New portable antenna towers, as point-to-point radio communications, are a way to mitigate the communication when cellular infrastructures are unavailable. But their deployment requires time decreasing the likelihood of finding people alive in the following of such events. In this work, we present the architecture of Floater, a mobile application that implements opportunistic communication for context-aware services in post-disaster scenarios. Floater is based on Floating Content, an opportunistic communications paradigm that geographically constrains message replication. We implement Floater using Google Nearby API that enables seamless nearby interactions without having to be connected to the Internet. Moreover, we provide the implementation notes and the comparison of the technologies adapted with the respect of the state-of-the-art.
Falko Dressler, Florian Klingler, Gianluca Rizzo
Proceedings of the 5G Italy global meeting "The 5G Italy Book 2019: a Multiperspective View of 5G "
The evolution of current wireless access networks towards 5G and beyond is characterized, among others, by the provisioning of high-bandwidth services and by the capability of serving traffic of a large number of heterogeneous devices. Among the key approaches for provisioning high capacity in such networks, a prominent role is played by network densification. However, dense deployments of many small cell base stations imply huge investments, increasing both CAPEX and OPEX for the mobile network. Additionally, densification increases the amount of overprovisioned network resources, due to variability in traffic demand over space and time. One of the most promising approaches to address these issues is the moving network paradigm, which exploits vehicle-mounted small cell moving base stations. This allows taking advantage of the correlation between spatio-temporal patterns of users and of vehicles, in order to create a network that flexibly and naturally densifies whenever and wherever needed by “following” users, hence reducing the need for dense deployments of static base stations. In this chapter, we review the main motivations and drivers for integrating moving base stations into future cellular access networks, and we outline the overall network architecture resulting from such integration. Furthermore, we characterize some of the main open research issues which stand in the way of the practical feasibility of the moving network paradigm. Among these are questions such as how to efficiently manage network resources in a dynamic fashion, accounting for the dynamics of service demand as well as of the moving network infrastructure; how to mitigate interference effects; how to implement mechanisms for reliable wireless mobile backhaul, for the interconnection of moving base stations to the core of the network; and how to efficiently provision Multi-access Edge Computing (MEC) services in the moving network paradigm.
Gaetano Manzo, Sebastian Otálora, Marco Ajmone Marsan, Torsten Braun, Hung Nguyen, Gianluca Rizzo
Proceedings of the ITC 31- Networked Systems and Services 2019
Opportunistic communications are expected to play a crucial role in enabling context-aware vehicular services. A widely investigated opportunistic communication paradigm for storing a piece of content probabilistically in a geographical area is Floating Content (FC). A key issue in the practical deployment of FC is how to tune content replication and caching in a way which achieves a target performance (in terms of the mean fraction of users possessing the content in a given region of space) while minimizing the use of bandwidth and host memory. Fully distributed, distance-based approaches prove highly inefficient, and may not meet the performance target, while centralized, model-based approaches do not perform well in realistic, inhomogeneous settings. In this work, we present a data-driven centralized approach to resource-efficient, QoS-aware dynamic management of FC. We propose a Deep Learning strategy, which employs a Convolutional Neural Network (CNN) to capture the relationships between patterns of users mobility, of content diffusion and replication, and FC performance in terms of resource utilization and of content availability within a given area. Numerical evaluations show the effectiveness of our approach in deriving strategies which efficiently modulate the FC operation in space and effectively adapt to mobility pattern changes over time.
Christian Esposito, Antonios Gouglidis, David Hutchison, Andrei Gurtov, Bjarne E. Helvik, Poul E. Heegaard, Gianluca Rizzo
Proceedings of EuCNC 2018
Network communications and the Internet pervade our daily activities so deeply that we strongly depend on the availability and quality of the services they provide. For this reason, natural and technological disasters, by affecting network and service availability, have a potentially huge impact on our daily lives. Ensuring adequate levels of resiliency is hence a key issue that future network paradigms, such as 5G, need to address. This paper provides an overview of the main avenues of research on this topic within the context of the RECODIS COST Action.
Gianluca Rizzo, Zhan Liu
Proceedings of the15th IEEE Annual Consumer Communications & Networking Conference (CCNC) 2018
In this work, we demonstrate the feasibility and the main functionalities of a low-cost, nomadic platform for Smart District services. The goal of the platform is to enable the extension of Smart City services to smaller cities, to towns and into the countryside, bypassing the natural barriers through the use of services and vectors which are naturally cross-domain, such as public transportation vehicles, and moving people. the platform is based on mobile and opportunistic sensing, on crowdsensing, and on strategies for community engagement and co-creation mediated by a map-based crowdsourcing application. The demo will showcase the main components of the system, as well as a sample set of Smart District services supported by the platform.
Gianluca Rizzo, Marco Ajmone Marsan
Proceedings of the 10th International Conference on Communication Systems & Networks (COMSNETS) 2018
In this paper we study static and dynamic ap- proaches to energy efficiency in dense cellular networks, where interference is one of the main limiting factors. We consider the two main approaches to energy efficiency through adaptive management of the network capacity: Base station (BS) sleeping and cell zooming. We propose an analytic framework for the assessment of the energy efficiency potential of several joint planning and management strategies. Our approach is based on stochastic geometry tools, on an approximate but accurate model of interference, and on a detailed, measurement-driven power model. For a given user density, we show how to derive the optimal BS density, and the BS transmit power which minimizes the mean power consumption of the network, while achieving a target QoS level. Through numerical evaluations, we show the potential savings enabled by joint (and disjoint) optimization of transmit power and density of active BSs. For a realistic network scenario, our approach suggests that huge energy savings are achievable by combining sleeping and zooming. In addition, we show that a static strategy, based on carefully planning the density of installed BS and their transmit power, can achieve most of the benefits of capacity tuning achievable through either sleeping or zooming. This result has a very high relevance for network operators, since it allows avoiding the feared decrease in operational lifetime which the daily switching of BS entails.
Proceedings of International Teletraffic Congress (ITC) 29 conference
Among the proposed opportunistic content sharing services, Floating Content (FC) is of special interest for the vehicular environment, not only for cellular traffic offloading, but also as a natural communication paradigm for location-based context-aware vehicular applications. Existing results on the performance of vehicular FC have focused on content persistence, without addressing the key issues of the effectiveness with which content is replicated and made available, and of what are the conditions which enable acceptable FC performance in the vehicular environment. This work presents a first analytical model of FC performance in vehicular networks in urban settings. It is based on a variation of the random waypoint (RWP) mobility model, and it does not require a model of road grid geometry for its parametrization. We validate our model extensively, through numerical simulations on real-world traces, showing its accuracy on a variety of mobility patterns and traffic conditions. Through analysis and simulations, we show the feasibility of the FC paradigm in realistic urban settings over a wide range of traffic conditions.
Gaetano Manzo, Ridha Soua, Antonio Di Maio, Thomas Engel, Maria Rita Palattella, Gianluca Rizzo
Proceedings of the 8th International Workshop on Mobility Management in the Networks of the Future World (MobiWorld 2017)
The increasing interest in vehicular communications draws attention to scalability and network congestion problems and therefore on techniques to offload the traffic, typically carried through the infrastructure, to the Vehicle-to-vehicle (V2V) network. Floating content (FC) represents a promising paradigm to share ephemeral content without direct support from infrastructure. It is based on constraining geographically within the Anchor Zone (AZ), the opportunistic replication of a given content among vehicles, in a way that strikes a balance between minimization of resource usage and content availability to users within the AZ. This paper constitutes a first attempt at addressing the issue of how to control FC performance in a realistic vehicular setting. It proposes a set of strategies for tuning the size of the AZ, based on the estimation of some key mobility parameters and of target FC performance.
Antonio Di Maio, Ridha Soua, Maria Rita Palattella, Thomas Engel, Gianluca Rizzo
Proceedings of the 14th Annual IEEE Consumer Communications & Networking Conference 2017
Floating Content (FC) has recently been proposed as an attractive application for mobile networks, such as VANETs, to operate opportunistic and distributed content sharing over a given geographic area, namely Anchor Zone (AZ). FC perfor-mances are tightly dependent on the AZ size, which in literature is classically chosen by the node that generates the floating message. In the present work, we propose a method to improve FC performances by optimizing the AZ size with the support of a Software Defined Network (SDN) controller, which collects mobility information, such as speed and position, of the vehicles in its coverage range.
Proceedings of the Modelling, Analysis and Simulation of Computer and Telecommunication Systems (MASCOT) 2016
Network densification is currently seen as one of the key techniques enabling Radio Access Networks (RANs) to meet the performance and functional requirements of the 5G paradigm in urban areas. Avoiding the connection of small cells to the power grid facilitates their deployment and reduces both capital and operational expenditures (CAPEX and OPEX). In this paper, we propose an approach to enable net-Zero Energy Networking (ZEN) in urban scenarios, based on dynamically managing the operating point of Base Stations (BSs), so as to drastically decrease their overall energy requirements. More specifically, we formalize the problem of optimizing the CAPEX of a ZEN, while guaranteeing quality of service (QoS) and a given level of service availability. Optimization is over power system parameters (solar panel area, battery capacity) as well as over BS power levels and user association over time. We propose a practical algorithm for the derivation of QoS-aware spatio-temporal strategies in terms of user association and BS power allocation, which, for a given expected pattern of renewable power generation, minimize the probability of service unavailability due to power shortage. Through extensive simulations using measured data, and realistic BS deployments, we show that our algorithm leads to substantial reduction in CAPEX, and to feasible power system requirements.
Gianluca Rizzo, Gaetano Manzo, et al.
Proceedings of 8th EAI International Conference on Ad Hoc Networks (ADHOCNETS) 2016
Content dissemination in Vehicular Ad-hoc Networks has a myriad of applications, ranging from advertising and parking notifications, to traffic and emergency warnings. This heterogeneity requires optimizing content storing, retrieval and forwarding among vehicles to deliver data with short latency and without jeopardizing network resources. In this paper, for a few reference scenarios, we illustrate how approaches that combine Content Centric Networking (CCN) and Floating Content (FC) enable new and efficient solutions to this issue. Moreover, we describe how a network architecture based on Software Defined Networking (SDN) can support both CCN and FC by coordinating distributed caching strategies, by optimizing the packet forwarding process and the availability of floating data items. For each scenario analyzed, we highlight the main research challenges open, and we describe a few possible solutions.
Proceedings of the 30th IEEE International Conference on Advanced Information Networking and Applications (AINA) 2016
The surging interest in autonomous coordinateddriving and in proactive safety services, exploiting the wealth ofsensing and computing resources which are gradually permeatingthe urban and vehicular environments, is making provisioning ofhigh levels of QoS in vehicular networks an urgent issue. At thesame time, the spreading model of a smart car, with a wealthof infotainment applications, calls for architectures for vehicularcommunications capable of supporting traffic with a diverse setof performance requirements. So far efforts have been revolvedtowards enabling a single specific QoS level. But the issues of howto support traffic with tight QoS requirements (no packet loss, and delays inferior to 1ms), and of designing a system capable atthe same time of efficiently sustaining such traffic together withtraffic from infotainment applications, are still open. In this paper we present the approach taken in the SNFCONTACT project in order to tackle these issues. The goal ofthe project is to investigate how an architecture for vehicularcommunications which integrates content-centric networking, software-defined networking as well as context aware floatingcontent schemes can properly support the very diverse set ofapplication and services currently envisioned for the vehicularenvironment.
2015
Gianluca Rizzo, Christian Vitale, Balaji Rengarajan, Vincenzo Mancuso
Proceedings of the 27th International Teletraffic Congress (ITC) 2015
We consider a queuing system with coupled processors (CPS), in which the service rate at each queue varies over time in function of the set of active queues in the system. Performance analysis of CPS has so far been based on simulations or on complex Markov chains under restricting assumptions on input traffic statistics. In contrast, we propose a fully analytical approach to CPS, based on a worst case analysis of system dynamics, and applicable to a large family of traffic characterizations. We derive sufficient conditions for stability for traffic characterized stochastically as well as for traffic constrained by arrival curves, and we show how to compute bounds on backlog and delay. We illustrate our approach and assess our results by means of an example of coupling of wireless transmissions.
Gianluca Rizzo, Alex Carmine Olivieri
Proceedings of The 9th International Conference on Innovative Mobile and Internet Services in Ubiquitous Computing (IMIS) 2015
The Internet of Things (IoT) opens new perspectives for the Machine-To-Machine communications, as it brings to settings with a large and heterogeneous set of devices. This makes integration of such diverse technologies a challenging task. A typical solution to this problem is represented by universal gateways, which provide internal semantics for protocol translation. However such approach is bound to be challenged in future IoT scenarios, as it brings substantial performance impairments in settings with very large number of devices and of technologies. We address these limitations, by proposing two novel approaches. A first is based on distributing the management of the different technologies among gateways. A second approach makes use of Web Service delegation, with gateways acting only as a connecting point between the entities and some service that can interpret the information exchanged. We implement and validate experimentally these approaches, showing that they both scale sensibly better than the traditional approach, guaranteeing acceptable performance even with a high degree of heterogeneity. Moreover, we identify the criteria which should be considered when choosing between the two proposed approaches. Our results establish a set of guidelines for integration in large and heterogeneous IoT scenarios.
Gianluca Rizzo, Mancuso Vincenzo, Christian Vitale
Proceedings of International Conference on Communications (ICC) 2015
In this paper we present an analytic approach to performance analysis of ad hoc networks under non saturation conditions, which does not rely on any assumption on traffic statistics. Our approach assumes traffic to be constrained by leaky bucket arrival curves, and it relies on a coupled processors model to capture the dependencies between user achievable rates due to sharing of the wireless transmission medium. We derive sufficient conditions for stability of transmission queues in an ad hoc network, and we describe a method for the determination of a proportionally fair allocation of resources, which allows trading the fairness of the solution for computational complexity. We validate our results through simulations, showing how our approach allows deriving operating points which both increase the fairness of the allocation and the overall average utilization of network resources with respect to saturated models.
Gianluca Rizzo, Marco Ajmone Marsan, Vincenzo Mancuso, Shahzad Ali
Proceedings of IEEE Conference Computer Communications(INFOCOM) 2015
This work presents the first experimental evaluation of the Floating Content (FC) communication paradigm in a campus/large office setting. By logging information transfer events we have characterized mobility patterns, and we have assessed the performance of services implemented using the FC paradigm. Our results unveil the key relevance of group dynamics in user movements for the FC performance. Surprisingly, in such an environment, our results show that a relatively low user density is enough to guarantee content persistence over time, contrarily to predictions from available models. Based on these experimental findings, we develop a novel simple analytical model that accounts for the peculiarities of the mobility patterns in such a setting, and that can accurately predict the effectiveness of FC for the implementation of services in a campus/large office setting.
Gianluca Rizzo, Alex Carmine Olivieri, Francois Morard
Proceedings of the 29th International Conference on Advanced Information Networking and Applications Workshops (WAINA) 2015
The integration of different protocols and technologies remain to date one of the main challenges in IoT. The lack of widely accepted standards at the application layer, and the wide deployment basis of a large number of legacy (e.g. Non-IP) technologies further exacerbate this issue. To date, typically integration is solved with ad hoc solutions on a per-connection basis ("N-to-N"). Such approach does not scale, being suitable only for small scenarios with a limited heterogeneity of technologies. More scalable approaches have been proposed, message-based, and built around a publish-subscribe architecture. In this work we summarize an experimental evaluation of such integration approach, based on the implementation of a Smart Office use case. We describe in detail the main integration issues arisen, and how they have been addressed. Our work shows how to integrate in practice in an efficient and scalable manner highly heterogeneous IoT scenarios.
Gianluca Rizzo, Vincenzo Mancuso, Christian Vitale
Proceedings of the Conference on COmmunication systems and networks (COMSNETS) 2015
This paper presents a first fully analytical approach to performance evaluation of D2D communication systems, which does not assume the system to be in saturated conditions. We adopt a Coupled Processors model to describe a cellular scenario with D2D users sharing radio resources with cellular users, i.e., adopting in-band underlay D2D schemes. We derive sufficient conditions for stability of such system, characterizing the effect of D2D transmissions on cellular user performance. Moreover, we present a computationally feasible method for the determination of a proportionally fair allocation of resources. We show that, in non-saturated networks, such an allocation sensibly improves the one derived under the assumption of saturation. Our results show the importance of accurately modelling the interdependence in users performance in the design and evaluation of a D2D cellular system.
Antonio Jara, Luc Dufour, Dominique Genoud, Gianluca Rizzo, Pierre Roduit, Jean-Jacques Bezian, Bruno Ladevie
Proceedings of the 8th International Conference on Innovative Mobile and Internet Services in Ubiquitous Computing 2014
In order to enable demand response schemes for residential and industrial users, it is crucial to be able to predict and monitor each component of the total power consumption of a household or of an industrial site over time. We used the cross-validation method which is a model validation technique for assessing how the results of a statistical analysis will generalize to an independent data set. It is mainly used in settings where the goal is prediction, and one wants to estimate how accurately a predictive model will perform in practice. We exploit Non-Intrusive Load Monitoring (NILM) techniques in order to provide behavior patterns of the variables identified. This work presents a review Non-Intrusive Load Monitoring (NILM) techniques and describe the results of recognition patterns used for the identification of electrical devices. The proposed method has been validated on an experimental setting and using direct measurements of appliances consumption, proving that it allows achieving a high level of accuracy in load disaggregation.
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