Task placement optimization in cloud-edge-fog environments is a challenging problem that requires balancing multiple objectives, such as minimizing latency and energy consumption, while adhering to resource constraints. This paper proposes a framework that integrates Deep Reinforcement Learning with Graph Neural Networks to address these challenges. Specifically, we explore the effectiveness of such architectures, including Graph Convolutional Networks and Message Parsing Neural Networks, within a DRL agent for task allocation. The framework is evaluated on synthetic task flow graphs, representing parallel workflows of varying complexities ($\mathbf{1 0}$and$\mathbf{1 0 0}$tasks), and benchmarked against traditional methods such as Genetic Algorithms and a Random Agent. Our results demonstrate that the RL Agent with GCN layers outperforms the MPNN-based RL Agent, GA, and Random Agent in small-scale scenarios while it performs equivalently with the MPNN-based RL Agent in largescale scenarios in which both surpass the heuristic approach and the Random agent.

The work reflects about the importance of trust in data exchanges in the context of ever-increasing distributed computing ecosystems. It proposes the utilisation of an open-source technology that implements a direct acyclic graph incorporating peer nodes to validate messages in a decentralised network. The tool, IOTA, promises to solve the hindrances of blockchain solutions in highly heterogeneous, IoT-assimilable scenarios, adopting a more lightweight approach, removing the need of mining. The article explores the functioning of IOTA in distributed computing continuum cases, understanding the figures and mechanisms that govern the process. The authors link those reflections to the direct transfer into a research project, aerOS, that uses such a tool as intrinsic part of an IoT-Edge-Cloud continuum framework, enabling the immutability and non-repudiation of key messages in such environments. Also, the authors conclude analysing which next steps might follow to evolve from a not-fully decentralised implementation with the next releases of the tool, and the adaptations for the studied application.

There is great potential in leveraging Artificial Intelligence (AI) systems to optimize complex infrastructures, automate difficult tasks, or support autonomy and coordination between networked devices. However, advances in state-of-the-art AI often neglect features and/or requirements that businesses care deeply about, namely traceability and explainability. While majority of research concerning Explainable AI remains focused on weight modelling and timid gray-box approaches, the state-of-the-art has not explored much the deployment of semi-physical architectures combining fuzzy rule-based systems with more opaque models to improve explainability. This contribution aims to explore and make the case for a middle ground of mixed AI architectures that combine the performance of black-box AI models with a more explainable overall architecture, enabling operators to use them, while still retaining the core aspects of explainability, when compared to full black-box AI systems. This work contextualizes a potential application of such approach to the problem of Service Level Agreement compliance, in a case of microservice allocation decision over cloud (and cloud-like) infrastructures.

[EN] Digital Twins are software technologies that enable the modelling of real-world phenomena in digitised environments, representing and monitoring the reality of various processes, including IoT deployments. Since 2017, the use of Digital Twins has been increasing. However, in the road transport and logistics realm, the adoption rate remains low, primarily due to the costs of processing and validating data in centralised scenarios, among other factors. On the other hand, Blockchain technologies were created to provide immutable and decentralised data storage in diverse scenarios, adding a layer of isolation and reliability in heterogeneous solutions. This paper presents a case study proposing a Digital Twin based on open-source Blockchain technologies, such as FIWARE Canis Major. The primary goal is to design and implement a robust and efficient open-source architecture that allows for the control and optimisation of vehicle fleet allocations in logistics/transport companies within supply chain management. This case study aims to showcase the practical application of the proposed solution in a real-world context, providing insights into its eco-friendly and low-cost attributes while opening the door to a large number of additional applications.

The aim of this contribution is to analyse practical aspects of the use of REST APIs and gRPC to realize communication tasks in applications in microservice-based ecosystems. On the basis of performed experiments, classes of communication tasks, for which given technology performs data transfer more efficiently, have been established. This, in turn, allows formulation of criteria for the selection of appropriate communication methods for communication tasks to be performed in an application using microservices-based architecture.

New requirements, posed by the Next Generation IoT, demand design of novel reference architectures, providing foundation for implementation of Internet of Things (IoT) ecosystems. Building on cloud-native concepts (e.g. microservices, virtualisation, and containerization), a flexible architecture that answers requirements present in recent IoT deployments is introduced. A general description of components of the architecture (grouped in horizontal planes and vertical capabilities) is provided, together with formal definition of architectural views. Moreover, ground is laid for upcoming validation in real-world-anchored scenarios. Functional, node, deployment and data views are presented, each of them addressing concerns of different stakeholder groups, typically involved in an IoT deployments.

In this work, the development of virtual reality software for “industrial applications” is considered. It is argued that, in this context, the vast experience from the development of computer games cannot be used directly. Especially, the specific nature of solutions dedicated to industrial applications requires taking into account their specificities, needs, and limitations of VR. This brings about the formulation of a domain-specific approach to creation of VR-related courses for the industry. As an example, the development of course concerning the operation of a professional 3D printer, which is used in industry, as well as in prototyping, is discussed. In particular, it is used to illustrate implementation of UI and UX aspects of the developed VR-environment.

The average life expectancy of the world’s population is increasing and the healthcare systems sooner than later will be compromised by its reduced capacity and its highly economic cost; in addition, the age distribution of the population is leading towards the older spectrum. This trend will lead to immeasurable and unexpected economic problems and social changes. In order to face up this challenge and complex economic and social problem, it is necessary to rely on the appropriate digital tools and technological infrastructures for ensuring that the elderly are properly cared in their everyday living environments and they can live independently for longer. This article presents ACTIVAGE IoT Ecosystem Suite (AIoTES), a concrete reference architecture and its implementation process that addresses these issues and that was designed within the first European Large Scale Pilot, ACTIVAGE, a H2020 funded project by the European Commission with the objective of creating sustainable ecosystems for Active and Healthy Ageing (AHA) based on Internet of Things and big data technologies. AIoTES offers platform level semantic interoperability, with security and privacy, as well as Big Data and Ecosystem tools. AIoTES enables and promotes the creation, exchange and adoption of cross-platform services and applications for AHA. The number of existing AHA services and solutions are quite large, especially when state-of-the-art technology is introduced, however a concrete architecture such as AIoTES gains more importance and relevance by providing a vision for establishing a complete ecosystem, that looks for supporting a larger variety of AHA services, rather than claiming to be a unique solution for all the AHA domain problems. AIoTES has been successfully validated by testing all of its components, individually, integrated, and in real-world environments with 4345 direct users. Each validation is contextualized in 11 Deployment Sites (DS) with 13 Validation Scenarios covering the heterogeneity of the AHA-IoT needs. These results also show a clear path for improvement, as well as the importance for standardization efforts in the ever-evolving AHA-IoT domain.

Lack of interoperability between devices is a key aspect of IoT application development where different heterogeneous devices are intended to seamlessly interoperate. Moreover, if we focus on implementing the interaction and interconnection between devices and standard IoT platforms, the challenge is even more complex because of the inherent heterogeneity in the protocols, technologies, and data formats supported by each device. To solve this problem, we propose an interworking architecture based on the oneM2M standard through the implementation of an Interworking proxy entity (IPE) that acts as a middleware between the heterogeneous IoT devices and oneM2M-based IoT systems. The functionality of the architecture is validated through a scenario applied to port transport and logistics.

The flexibility and programmability offered by Software Defined Networking (SDN) emerge as an approach to resolve some of the main challenges that the Internet of Things (IoT) deployments expose. In the present article, we explore the application of SDN components onto IoT deployments, together with the decoupling of typical gateway functions in two realms; the physical one and the virtual at the edge. This disengagement is a novel approach necessary since the computation resources on the physical part of the infrastructure are limited. Thus, the more resource-consuming processes are transferred to the edge of the network, in the virtual counterpart of the gateway. Additionally, within this infrastructure, different network applications can be running at the top of the SDN controller, in the control plane, for example, QoS policies application, management of network parameters, etc. Providing a holistic view of the IoT deployment. Between its advantages, this work focus on the ease of creation of an IoT infrastructure with the gateway and SDN architecture, and the behaviour of the IoT system. For validation, a small setup scenario and a use case is created where heterogeneous IoT sensors communicate with the physical part of the gateway, implemented with a Raspberry Pis and this, with its virtual part at the edge of the network, so finally sent the data to an IoT platform (FIWARE-ORION) at the core network managed by a virtual Switch (OpenVSwitch) and a RYU-based SDN controller.

Applications and Services are located at the top of the IoT deployments and represent a big portion of the IoT stack. Each Platform has several IoT Services and these use to be domain-oriented and very heterogeneous. This heterogeneity hinders the interoperability between services and applications from different IoT Platforms. Flow Based Programming is a paradigm that allows the interconnection of services and the creation of an execution flow between them. There are several solutions that use this paradigm within the IoT platforms, but none is mainly focused in the aim of connect services from different IoT platforms. To address this, a methodology is described to develop functionalities to access to the services, and an architecture is provided with different components to offer a solution to this interoperability problem. This solution offers advantages in the registry, cataloging and discovery of services, and in the creation and management of composite IoT Services. Finally, this paper show a use case related with transport and logistic to validate this approach.

Chronic Obstructive Pulmonary Disease (COPD) is a wide concept to describe a group of diseases which affect a normal respiratory function and cause a considerable impact on patients' life quality and healthcare costs. There are few IoT systems in the present literature that are focused on monitoring and management of COPD patients, but they are not focused on the vast amount of data that IoT generates in a large scale deployment, and the integration of Smart City services. For these reasons, this paper presents an innovative system based on Cloud Computing and Big Data technologies to integrate Smart City services into a large scale scenario. To do so, this system proposes a Big Data architecture based on Apache Spark libraries to provide data integration, storage, descriptive and predictive analysis. Also, the system provides a web interface application where users can visualize the data analysis results. They show that the data enrichment function performed on the Big Data architecture provides more information about the environment to improve decisionmaking. This way, the system helps COPD patients to get more involved into decision making process and promote an active and healthy life by recommending the least polluted area to performance their daily activities.

From the general SOA architectural pattern, through distributed computing based on Grids and Clouds, to the Internet of Things, the idea of collaboration between software entities, independent from their vendors and technologies, attracts much attention. This brings about a question: how to achieve interoperability among multiple (existing and upcoming) platforms/systems/applications. The context for the presented research is provided by the INTER-IoT project, which deals with different aspects of interoperability in the Internet of Things (IoT). It aims at the design and implementation of an open framework and associated methodology to provide interoperability among heterogeneous IoT platforms, across a software stack (devices, network, middleware, application services, data and semantics). We focus on the data and semantics layer. Specifically, the role of ontologies and semantic data processing, as means of achieving interoperability. However, since the vision of the Semantic Web remains mostly unfulfilled, semantics remains implicitly “hidden” data and in exchanged messages. Therefore, we are particularly interested in establishing what methods and tools exist to create OWL ontologies from implicitly expressed semantics. We focus on popular data formats i.e. XML, JSON, RDF, Relational Databases and NoSQL Databases.

Ambient Assisted Living (AAL) represents one of the most promising Internet of Things (IoT) applications due to its influence on the quality of life and health of the elderly people. However, the interoperability is one of the major issues that needs to be addressed to promote the adoption of AAL solutions in real environments. In this paper, an IoT prototype system for AAL called AAL-IoTSys is proposed, which includes a Smart IoT Gateway as a key component to enable the interoperability from several heterogeneous devices over different communication protocols and technologies (e.g., WiFi, ZigBee, Bluetooth, IEEE 802.15.4, 6LowPAN). This system aims to monitor environmental (temperature, humidity, C02), health (heart rate) and location (GPS) parameters in the elderly people's houses in order to facilitate events early detection and automatic sending notifications to elderly care stakeholders in active and healthy aging scenarios (included health professionals, caregivers, family members and emergency services).

Internet of Things (IoT), more than smart homes and connected appliances, is to reach physical knowledge in real-time and remotely; and taking advantage of the smartphone’s increasing diffusion, it is possible using its embedded sensors to monitor the environment, anytime and anywhere; this could be the solution to many community problems as well as natural hazards. This paper focuses on the solution to one of the most deadly natural hazards, earthquakes; taking seismic data of Ecuador, a country with an average of 6 earthquakes per day in 2013. Technologies of IoT like Sensor Web Enablement Framework (SWE) and Message Queue Telemetry Transport (MQTT) give the benefit of achieving an Early Warning System capable of anticipating up to 12 seconds the maximum seismic peak in the epicentre zone through smartphones. The system is supported by a wireless sensor network and its main components, requirements and design decisions are described. It considers time and spatial analyses, not present in any other work, making it more precise and customizable, and adapting it to the features of the geographical zone and resources. A preliminary evaluation of the solution was conducted to determine its strengths and weaknesses in terms of response time. The obtained results indicate that the energy consumption is as relevant for end-users as their personal security.

Wireless sensor and actuator networks play an important role in the Internet of Things (IoT) as they are key for the creation of Pervasive Smart Environments. These networks are developed through the interconnection of various heterogeneous devices. Due to the heterogeneity of the devices in terms of the communication protocols and the technologies used, the interconnection between them is still difficult. Particularly, interconnection and interoperability in IoT are two of the great challenges that needs to be faced in order to implement pervasive smart environments. We present the design and implementation of a Smart IoT Gateway which allows technical and syntactic interoperability in IoT using standard open protocols and standard data representation formats. We evaluated and demonstrated the effectiveness of the Smart IoT Gateway in terms of interoperability through its application to a use case in the industry sector.

Sensor Networks are increasingly playing a fundamental role in many application scenarios such as agriculture, maritime, healthcare, industrial and even military application. However, the high heterogeneity of sensor networks poses a great challenge in interoperability and cooperative work, and the building of technological bridges among wireless sensor network (WSN) islands is more and more a must for smart cities for an efficient operation. In this paper, we present a model for an Area Sensor Network (ASN) that combines and connects small networks (Body Sensor Networks), WSNs and even fixed sensor networks within a particular area of interest. Initial tests show that the combination of sensed data from multiple sources (sensor networks) produces synergetic services useful for smart cities.

Designing and testing large sensors networks can be performed by means of simulation tools. They facilitate faster tests without risks and also with reduced operational costs. Sensor networks are used in many environments, typically outdoors. In this paper we present the use of a high level sensor simulator and sensor web standards applied to an indoor industrial environment, in order to target worker's safety. The FASyS (Fabrica Absolutamente Segura y Sostenible) CENIT project has as key challenge the continuous monitoring of industrial workers in order to proactively detect risks. For this, we developed a simulator representing multiple types and number of sensors and integrate it with a standard sensor database known as Sensor Observation Service (SOS). Furthermore, we develop a Human Computer Interface (HMI) to monitor all sensors and also a Control Center application to test one of the risks within the factory (collision detection).

Context-aware and live multimedia content production and delivery can be considered as key issues for enabling dynamic sharing among members of living social networks. The proposed cross-platform environment, deployed on J2ME technology, enables mobile users with a suitable tool for content production, dynamic context and metadata integration and content publication directly from smart devices. Multimedia content is provided with an extensible semantic and functional data model that makes shared content easily to be catalogued, classified and managed within large scale communities. Moreover, an advanced context management model provides users with multiple options for effective content publication. Support for live streaming and potential interaction with multiple social communities makes the platform really flexible within different domains and application fields.

Current military command and control information systems aim is to elaborate the common operational picture (COP) focused on the higher hierarchical levels, from battalion level and upwards. However, in majority of present conflicts, including peacekeeping missions, many operations are carried by small units like platoons and downwards. It would be extremely useful a command and control tool which: (i) allows obtaining the COP at platoon and squad level; (ii) facilitates command and control decisions from different tactical locations; (iii) allows shared awareness based self-synchronization among platoons and (iv) acquires individualized data from troop units, particularly video flows and geolocation. In this paper, a practical research in this field is described based on the development of a command, control, computers, communications, intelligence, surveillance and reconaissance (C4ISR) multimedia system designed to proof the most advanced concepts in current C2IS (command and control information systems) development.

Urban traffic control systems have based their technological infrastructure on both advanced analogical close-circuit television systems (TVCC) and point-to-point links, providing low-scalable and very expensive systems. The main goal of an urban traffic monitoring system is to capture, send, play and distribute video information from the streets of a certain city. Current digitalization process of video networks, and the research carried out in the field of streaming media, has led vendors to present proprietary hardware and software solutions resulting in a strong dependency among their customers. The existence of open standards for video encoding and protocols for streaming media transmission over IP networks has led us to propose this system. The work presents an open urban traffic control system which bases its design on COTS philosophy for hardware and software, as well as open source and standardized protocols. The proposed system is a suitable solution in terms of scalability, cost, interoperability and performance for traffic control systems. Furthermore, its architecture can be easily adapted to other video applications and tools

We propose to adapt the scalable schema of content delivery networks (CDN) to the campus environment, naming the novel architecture as campus content delivery network (CCDN). This overlay network will provide scalable and balanced access to the students and teachers to e-learning facilities. The CCDN will be composed by caches used as edge delivery nodes, content routing capabilities to route the client to the closest copy of the content, distributed content distribution and management and improving the access of users in terms of speed, reliability, scalability and prevention of flash-crowds. We present as a case study the work in progress of the deployment of a CCDN in the technical university of Valencia together with an e-learning streaming application over the CCDN.

Assessing of the physical condition of the human body, and concretely musculoskeletal disorders, frequently requires evaluating different tests performed by different devices. This information has to be analysed simultaneously to derive conclusions, and so a temporal relationship must be established between the data sources, Synchronization of the data sources of information is achieved by synchronising the clocks of computers connected in a local area network (LAN) by means of NTP. The added time-stamp is used to playback the data in a synchronised way. Although the proposed system is valid for any medical application in which data synchronisation is needed, it has been specifically used to capture, process, and analyse data generated by electromyographs, lumbar equipment, isotracks and video. Afterwards, the data can be distributed through Internet using a biomedia on demand (BoD) server. The whole system has been developed using JAVA and the Java Media Framework (JMF) libraries.

In this paper we present the design and development of a real-time e-learning system at the Polytechnic University of Valencia. The main novelty of this multimedia virtual classroom is the integration of Windows Media, Java Media Framework (JMF) and MPEG4 in a web-based environment. The communication network used in this real-time e-learning system is a satellite network for the multicasting of high-quality video from the teachers to the students using RTP, together with Internet/ISDN as return channel from the remote classrooms for low-quality video questions transmission. The system is fully operational and in the following year will be used as support for an e-learning co-operation project between Spain and South-America by a satellite communications operator.

Routing problems arise in several areas of distribution management and have been the object of study by mathematicians and operational researchers. We focus on auto-guided vehicles (AGVs) scheduling and guidance algorithm based on Monte Carlo simulation, and its execution under Windows NT as a real-time operating system verifying feasibility using the earliest deadline first (EDF) scheduling policy. For these purposes we simulate the environment in the laboratory prior to its real integration in the ceramic tile factory floor, working with mobile robots instead of AGVs (increasing in this way the flexibility and avoiding the outwork infrastructure) using Profibus Fieldbus Data Link (FDL) as the fieldbus communication network.

New real-time applications like videoconference and video-on-demand as well as classical industrial and military hard real-time applications require a set of accurate services from transport protocols. Management of a global time reference in the network is one of them. Possibly, XTP will be one of the standard communication protocols for distributed real-time systems in a few years, due to its great variety of services and high performance offered. The authors propose the incorporation of a new service to the XTP offered set: the supply of a common time reference to a group of XTP users within the network. The proposed synchronization protocol to maintain this common time service works by wave sequence making use of the multicasting functionality of XTP 4.0. This proposed synchronization service maybe added to future XTP versions.