Edge systems are increasingly popular for data collection and processing. Typically, due to their limited storage capacity, pieces of data are continuously exchanged with Cloud systems which store them in distributed DataBase Management System (DBMS). This scenario, known as Cloud/Edge Continuum, is critical from a data security point of view as it is exposed to many risks. Transparent Data Encryption (TDE) is proposed as a possible solution for encrypting database files. However, current solutions do not suit the Cloud/Edge continuum requirements. In this paper, we aim at fulfilling this gap by proposing a solution to encrypt the data locally at the Edge and transfer them to a distributed database over the Cloud. Our approach allows us to perform queries directly on encrypted data over the Cloud and to retrieve them on the Edge for decryption. Experiments performed on different NoSQL DBMS solutions demonstrate the feasibility of our approach.

This paper focuses on a new approach to conceiving “virtual sensors” operating in smart environments, which are abstracted components able to map different behaviours on the same Internet of Things (IoT)-based infrastructures according to the needs of the high-level applications. To realize “virtual sensors”, it is necessary to codify user requests in an automation process for the deployment at the Edge of the microservices (MSs) that satisfy such requests. We present a solution that implements all the necessary functionalities to bind the user application with the Edge device in charge to execute the “virtual sensors”. In particular, the solution we propose is based on the FIWARE NGSI-LD information model, which helps us to standardize the communication among the different entities involved in the process. Moreover, the paper describes the reference architecture we designed, provides the implementation details of our first prototype and reports the results of our evaluation experiments.

The European project URBANITE (Supporting the decision-making in URBAN transformation with the use of disruptive Technologies) aims to put in place a sustainable mobility with the support of disruptive and innovative technologies for the sector of urban mobility. Urban mobility and smart mobility contexts, but not only, now require more than ever the use of large amounts of historical data to carry out the necessary analyses for different use cases. A good management of time series data, able to use pagination concepts in an optimized way and providing the user with specifications functions, therefore become indispensable. This need emerged as a native implementation in MongoDB 5.0. With the release of this version, users have functionality to manage time series collections. This new solution has stimulated us to undertake a study on the methods of managing time series data and compare the solution proposed by MongoDB with our solution based on the advanced use of the bucket approach. The two solutions were tested in a real context and the results obtained are reported in the paper.

The innovation process for the management of a Water Distribution Network (WDN) in a Smart City starts from an efficient digital representation of the network itself. This paper presents a new visualization tool for WDN that overcomes current challenges and provides water companies with useful managing information. Existing visualization tools are self-contained systems that work independently from other visualization software and do not provide real-time analysis of the pipes and water flow status in the WDN. Using digital maps such as Google Maps it is possible to extend the traditional digital representation of the WDN based on EPANET software. Moreover, the WDN representation can be enriched with localized information (e.g. roads or buildings superimposed on the WDN), that is useful for planning maintenance and structural services. In presence of a WDN equipped with sensors and flowmeters, the proposed tool can be used for optimized visualization of the flow rate and the condition of the pipes in real-time. For these reasons, this tool can be a powerful instrument to help technicians quickly identify problems in the WDN. In this work, we used synthetic data generation techniques to obtain a data-set of values that updated over time. Finally, to evaluate the designed solution, we implemented the proposed visualization tool and performed some experiments to test its effectiveness.

Nowadays, the Internet of Things (IoT) is widely adopted. To push-down costs, a possible solution can be represented by the large-scale adoption of low-cost sensors that, unfortunately, present several issues including sensor ageing that may cause, over time, failures in IoT systems due to erroneous collected data. In our opinion, a possible solution is IoT rejuvenation, a proactive cost-effective technique that can contrast the inevitable ageing of IoT systems guaranteeing the accuracy of collected data over time. Specifically, the purpose of this paper is to experimentally demonstrate the seriousness of the IoT ageing issue. To achieve such a goal, we consider a smart city scenario including intelligent street pole lamps equipped with low-cost ultrasonic sensors able to switch on lights when a vehicle is detected. Moreover, we pave the way toward IoT rejuvenation by discussing the perspectives of a Function as a Service (FaaS) based approach acting at the Edge.

Nowadays, video surveillance is a very common practice in Smart Cities. There are public and private video surveillance systems, and very often different systems or single devices frame the same area. However, when a target needs to be identified or needs to be tracked in real-time, such solutions typically require human intervention to configure the devices in the best possible way (e.g., choosing the optimal cameras, setting up their focus, and so on). To address such a problem, in this paper, we define a new interrogation method based on a Federated Edge approach. This approach addresses the problem from the point of view of both camera hardware and shooting angle associated with it. According to the presented approach, it is possible to understand which the best camera to identify a target and possibly tracking it in a specific area is. A case study is defined in the context of urban mobility management.

The usage of untrusted, non-certified or non-validated Internet of Things (IoT) devices can affect the entire system functioning, causing service interruption and invalidating information processing. These vulnerabilities are mainly due to the errors in providing services and the whole ecosystem's exposure to different cyber attacks. This paper aims to address these problems by proposing a new method to create a trusted distributed environment for implementing IoT services based on Edge computing. Our solution is based on the key idea that IoT devices are certified by a certification authority (CA) through an authorized broker. IoT devices will connect to the CA only if they have been previously authorized to the same. The CA will also allow single isolated IoT nodes to participate in one or more applications in a specific FIWARE-based domain. The entire certification process of IoT devices and the digital certificate issuance take place using a Mobile Edge Computing system (MEC) located near the IoT node. The MEC is the broker device that allows the interaction of the IoT device with the CA. We implemented the proposed solution and performed some experiments to test its effectiveness.

Smart environments are composed of an ever-increasing number of heterogeneous resources and devices for collecting and processing of a large amount of context data. These activities can be performed at the edge of the smart area, over a distributed and heterogeneous infrastructure, so to be close to the end-user and optimize response time. However, it is hard to define a data model able to support data exchange among different systems and between systems and users. This paper presents the key features of a smart environment and introduces the concept of virtual device, that is an abstracted component characterized by specific high-level functionalities. Then, the paper proposes a data model useful to represent and optimize the adoption of virtual device in smart environments. To better explain the data model features and benefits, we refer to a video surveillance use case, where a smart camera is able to provide the solid angle detection as a service.

Internet of Things has revolutionized the way services are distributed in smart environments, approaching the computation where data are generated. However, IoT devices have limited resources and reconfiguring them can be very difficult. In these cases, Edge computing represents a challenging solution supporting IoT with flexible management of resources. We investigate how pushing computation activities from Edge to IoT, changing the behavior of IoT nodes according to application or system requirements. We adopted the Multi-Hop-Over-The-Air update technology enabling the auto-configuration of IoT devices based on MicroController Units. Considering IoT nodes connected in a mesh network, we developed a distributed and collaborative ecosystem performing on-fly injection of code in IoT nodes, thus automatically deploying new services whenever necessary. We implemented a prototype of the proposed solution over a heterogeneous Edge-IoT mesh network and performed experiments with the purpose to study the update phase of end-devices while they execute Digital Signal Processing.

Sustainable mobility is a key objective for many Smart Cities. In this paper, we present an application for sustainable mobility that aims at encouraging citizens to use low-impact vehicles instead of private cars. Through a partnership between the University Messina and the Municipality of the Messina city (Italy), we developed MuoviME, a digital application to assign citizens electric bikes, free of charge for a limited period of time. The key issue we addressed in the development of such an application is security, both in terms of secure authentication of citizens that access the service and tracking of the whole assignment process, from the user's bicycle request to its restitution. To achieve this goal, we implemented a solution for the physical recognition of the user based on two-factor authentication (2FA) and Blockchain technology. This paper summarizes the secure by design approach, implementation details, and some experimental results on the service efficiency.

Tele-biomedical laboratory is a medical laboratory where blood exams are performed either by patients themselves in their homes or by biomedical technicians in satellite clinical centres through the Internet of Things (IoT) biomedical devices interconnected with Hospital Edge/Cloud systems that allow results to be sent to doctors belonging to federated hospitals for validation and/or consultation. This paper aims at providing a clear picture of the current state of the art in the tele- biomedical laboratory, also highlighting current issues and future challenges. Specifically, we start motivating the need for tele-biomedical laboratories adopting IoT, Edge and Cloud technologies. After a classification of the main biomedical equipment (considering connected, not-connected, invasive, minimally invasive and noninvasive devices), we present different possible tele-biomedical laboratory scenarios. In the end, we will discuss the recent issues, current feasibility and future challenges.