Nikolaos Georgantas

National Institute for Research in Computer Science and Control | INRIA · ARLES - Software Architectures and Distributed Systems Research Team

With the emergence of the Internet of Things (IoT), application developers can rely on a variety of protocols and Application Programming Interfaces (APIs) to support data exchange between IoT devices. However, this may result in highly heterogeneous IoT interactions in terms of both functional and non-functional semantics. To map between heterogen...

Numerous middleware application programming interfaces (APIs) and protocols were introduced in the literature in order to facilitate the application development of the Internet of Things (IoT). Such applications are built on reliable or even unreliable protocols that may implement different quality-of-service (QoS) delivery modes. The exploitation...

Online Social Network Services (OSNSs) are changing the fabric of our society, impacting almost every aspect of it. Over the past few decades, an aggressive market rivalry has led to the emergence of multiple competing, “closed” OSNSs. As a result, users are trapped in the walled gardens of their OSNS, encountering restrictions about what they can...

Civic engagement refers to any collective action towards the identification and solving of public issues. Current civic technologies are traditional Web-or mobile-based platforms that make difficult, or just impossible, the participation of citizens via different communication technologies. Moreover, connected objects sensing physical-world data ca...

To enable direct Internet connectivity of Things, complete protocol stacks need to be deployed on resource-constrained devices. Such protocol stacks typically build on lightweight IPv6 adaptations and may even include a middleware layer supporting high-level application development. However, the profusion of IoT middleware-layer interaction protoco...

Understanding the sensing context of raw data is crucial for assessing the quality of large crowdsourced spatiotemporal datasets. Detecting sensing contexts in the wild is a challenging task and requires features from smartphone sensors that are not always available. In this paper, we propose three heuristic algorithms for detecting sensing context...

Internet of Things (IoT) aim to leverage data from multiple sensors, actuators and devices for improving peoples' daily life and safety. Multiple data sources must be integrated, analyzed from the corresponding application and notify interested stakeholders. To support the data exchange between data sources and stakeholders, the publish/subscribe (...

Resource allocation for distributed systems is a well-known approach to deal with quality of service requirements. However, existing approaches do not consider the effects of resource allocation at the different levels of a system, especially when considering the end-to-end behavior of distributed compositions such as service choreographies. Based...

Mobile IoT applications are typically deployed on resource-constrained devices with intermittent network connectivity. To support the deployment of such applications, the Publish/Subscribe (pub/sub) interaction paradigm is often employed, as it decouples mobile peers in time and space. Pub/sub middleware protocols and APIs consider the Things' hard...

IoT systems are now being deployed worldwide to sense phenomena of interest. The existing IoT systems are often independent which limits the use of sensor data to only one application. Semantic solutions have been proposed to support reuse of sensor data across IoT systems and applications. This allows integration of IoT systems for increased produ...

IoT applications are usually characterized by large-scale demand and the widespread use of mobile devices. Similarly, performing interaction among application and system components in a decoupled and elastic way, and enforcing Quality of Service (QoS) usually also become issues. Hence, paradigms such as pub/sub on top of cloud resources represent a...

Internet-of-Things (IoT) protocols are constantly increasing in the research and industrial landscape. However, the current standardization efforts limit the incorporation of Things as first-class entities into choreographies. To tackle this interoperability barrier, we propose and demonstrate the eVolution Service Bus (VSB), a middleware solution...

Several domains have adopted the increasing use of IoT-based devices to collect sensor data for generating abstractions and perceptions of the real world. This sensor data is multi-modal and heterogeneous in nature. This heterogeneity induces interoperability issues while developing cross-domain applications, thereby restricting the possibility of...

Internet of Things (IoT) applications consist of diverse Things (sensors and devices) in terms of hardware resources. Furthermore, such applications are characterized by the Things’ mobility and multiple interaction types, such as synchronous, asynchronous, and streaming. Middleware IoT protocols consider the above limitations and support the devel...

Computer-mediated communication can be defined as any form of human communication achieved through computer technology. From its beginnings, it has been shaping the way humans interact with each other, and it has influenced many areas of society. There exist a plethora of communication services enabling computer-mediated social communication (e.g.,...

Systems deployed in mobile environments are typically characterized by intermittent connectivity and asynchronous sending/reception of data. To create effective mobile systems for such environments, it is essential to guarantee acceptable levels of timeliness between sending and receiving mobile users. In order to provide QoS guarantees in differen...

Service composition is a widely used method in ubiquitous computing that enables accomplishing complex tasks required by users based on elementary (hardware and software) services available in ubiquitous environments. To ensure that users experience the best Quality of Service (QoS) with respect to their quality needs, service composition has to be...

By bridging the physical and the virtual worlds, the Inter-net of Things (IoT) impacts a multitude of application domains, among which smart cities, smart factories, resource management, intelligent transportation, health and well-being to name a few. However, lever-aging the IoT within software applications raises tremendous challenges from the ne...

Internet-of-Things (IoT) protocols are constantly increasing in the research and industrial landscape. However, the current standardization efforts limit the incorporation of Things as first-class entities into choreographies. To tackle this interoperability barrier, we propose and demonstrate the eVolution Service Bus (VSB), a middleware solution...

Public transportation is essential for sustainable and economical development of cities. Several transport organizations aim to provide service information to commuters through web and mobile apps. This information includes possible routes between two stations, estimated travel and arrival times, and real-time updates about traffic conditions. Howe...

This document describes the dissemination and communication activities for the FIESTA-IoT project for the period M1 (February 2015) to M12 (January 2015). The dissemination plan is also presented, first describing how promotional material, FIESTA-IoT results, and FIESTA-IoT activities will be used to promote and engage with target communities in or...

With the emergence of Future Internet applications that connect web services, sensor-actuator networks and service feeds, scalability and heterogeneity support of interaction paradigms are of critical importance. Heterogeneous interactions can be abstractly represented by client-service, publish-subscribe and tuple space middleware connectors that...

Large-scale mobile environments are characterized by, among others, a large number of mobile users, intermittent connectivity and non-homogeneous arrival rate of data to the users, depending on the region's context. Multiple application scenarios in major cities need to address the above situation for the creation of robust mobile systems. Towards...

The smart cities of the future are expected to be serviced by advanced, personalized multimodal transit systems, charged with timely transport of citizens. Optimizing routes on such networks is a complex problem, in part due to the fact that simple metrics such as latency by themselves are not sufficient to find the best routes. In this paper, we f...

Transport in Senegal is chaotic and large, especially in main cities. Additionally, although most people have mobile phones, large part of them still rely on SMS. Considering this, we propose the development of an application platform for large-scale transport information management relying on ‘mobile social crowd-sensing’. To support this platform...

Modern software systems are often required to adapt their behavior at runtime in order to maintain or enhance their utility in dynamic environments. Models at runtime research aims to provide suitable abstractions, techniques, and tools to manage the complexity of adapting software systems at runtime. In this chapter, we discuss challenges associat...

With an increasing number of services and devices interacting in a decentralized manner, choreographies are an active area of investigation. The heterogeneous nature of interacting systems leads to choreographies that may not only include conventional services, but also sensor-actuator networks, databases and service feeds. Their middleware behavio...

This document describes the final implementation and the evaluation of the CHOReOS middleware. Evaluation is achieved both via the use of the middleware on CHOReOS use-cases and via synthetic experiments and simulation. The conclusion was that the implementation of the CHOReOS middleware has achieved a good level of maturity for an open source proj...

The essential issue of interoperability in distributed systems is becoming even more pressing in the Future Internet, where complex applications will be composed from extremely heterogeneous systems. Open system integration paradigms, such as service oriented architecture (SOA) and enterprise service bus (ESB), have provided answers to the interope...

The essential issue of interoperability in distributed systems is becoming even more pressing in the Future Internet, where complex applications will be composed from extremely heterogeneous systems. Open system integration paradigms, such as service oriented architecture (SOA) and enterprise service bus (ESB), have provided answers to the interope...

Quality of Service (QoS) in orchestrated web services compositions have been well studied with probabilistic and multi-dimensional models. Choreographies that involve message passing among services, on the other hand, require further analysis. In this paper, we begin with the set of QoS domains that may be studied in case of choreographies and the...

This is Part b of Deliverable D1.4, which specifies the final CHOReOS architectural style, that is, the types of components, connectors, and configurations that are composed within the Future Internet of services, as enabled by the CHOReOS technologies developed in WP2 to WP4 and integrated in the WP5 IDRE. The definition of the CHOReOS architectur...

The Future Internet environments raise challenging issues for the Service-Oriented Architectures. Due to the scalability and hetero-geneity issues new approaches are thought in order to leverage the SOA to support a wider range of services and users. The CHOReOS project is part of the European Community Initiative to sketch technological solutions...

Service-oriented Architecture (SOA) is one of the most recent trends in IT solutions. From a technical perspective SOA, can be considered a method for designing and developing IT systems where applications are constructed from loosely coupled and au-tonomous building blocks. For a thorough analysis and discussion of SOA at large, and of the applica...

Interoperability remains a fundamental challenge when connecting heterogeneous systems which encounter and spontaneously communicate with one another in pervasive computing environments. This challenge is exasperated by the highly heterogeneous technologies employed by each of the interacting parties, i.e., in terms of hardware, operating system, m...

Service-oriented computing is now acknowledged as a central paradigm for Internet computing, supported by tremendous research and technology development over the last 10 years. However, the evolution of the Internet, and in particular, the latest Future Internet vision, challenges the paradigm. Indeed, service-oriented computing has to face the ult...

While the development of CHOReOS systems build on well-known paradigms associated with service-oriented architectures (e.g., services, service bus and service choreography), the supporting architectural style re- quires accounting for the challenges posed by the future Internet, i.e., ultra large scale, high heterogeneity, increased mobility, and a...

This deliverable specifies the main concepts of the CHOReOS middleware architecture. Starting from the Future Internet (FI) challenges for scalability, heterogeneity, mobility, awareness, and adaptation that have been investigated in prior work done in WP1, we introduce the aforementioned concepts to deal with the requirements derived from the FI c...

This deliverable focuses on the design of the CHOReOS Integrated Development and Runtime Environment, aka CHOReOS IDRE, based on the supporting solutions developed within WP2, WP3 and WP4 during CHOReOS' 1st year. The document provides an overall description of the IDRE components, their respective functionalities and the integration dependencies b...

Integration of heterogeneous distributed systems becomes particularly challenging when these systems have diverse coordination models (e.g., client/server, publish/subscribe, tuple space). In this paper, we introduce a system integration solution based on orchestration workflow and a high-level data-driven coordination abstraction enabling applicat...

The D1.2 deliverable outlines the CHOReOS perspective on the Future Internet and its conceptualization. In particular, the deliverable focuses on: - Definition of the Future Internet and related Future Internet of Services and (Smart) Things, as considered within CHOReOS, further stressing the many dimensions underpinning the Ultra-Large Scale of t...

Interoperability remains a fundamental challenge when connecting heterogeneous systems which encounter and spontaneously communicate with one another in pervasive computing environments. This challenge is exasperated by the highly heterogeneous technologies employed by each of the interacting parties, i.e., in terms of hardware, operating system, m...

The D1.1 deliverable clarifies baseline, progress, and state of the art that CHOReOS will address. For each of the first four CHOReOS work packages, WP1 to WP4, this deliverable gives a precise definition of the state of the art, an indication of the envisaged progress beyond the state of the art by CHOReOS and the baseline for its research.

The Internet of Things plays a central role in the foreseen shift of the Internet to the Future Internet, as it incarnates the drastic expansion of the Internet network with non-classical ICT devices. It will further be a major source of evolution of usage, due to the penetration in the user’s life. As such, we envision that the Internet of Things...

Distributed systems are becoming more complex in terms of both the level of heterogeneity encountered coupled with a high level of dynamism of such systems. Taken together, this makes it very difficult to achieve the crucial property of interoperability that is enabling two arbitrary systems to work together relying only on their declared service s...

Current solutions to interoperability remain limited with respect to highly dynamic and heterogeneous environments, where systems encounter one another spontaneously. In this chapter, we introduce the Connect architecture, which puts forward a fundamentally different method to tackle the interoperability problem. The philosophy is to observe networ...

Interoperability is a fundamental problem in distributed systems, and an increasingly difficult problem given the level of heterogeneity and dynamism exhibited by contemporary systems. While progress has been made, we argue that complexity is now at a level such that existing approaches are inadequate and that a major re-think is required to identi...

Activity-oriented computing (AOC) is a paradigm promoting the run-time realization of applications by composing ubiquitous services in the user's surroundings according to abstract specifications of user activities. The paradigm is particularly well-suited for enacting ubiquitous applications. However, there is still a need for end-users to create...

Interoperability remains a fundamental challenge when connecting heterogeneous systems which encounter and spontaneously communicate with one another in pervasive computing environments. This challenge is exasperated by the highly heterogeneous technologies employed by each of the interacting parties, i.e., in terms of hardware, operating system, m...

Interoperability remains a fundamental challenge when connecting heterogeneous systems which encounter and spontaneously communicate with one another in pervasive computing environments. This challenge is exasperated by the highly heterogeneous technologies employed by each of the interacting parties, i.e., in terms of hardware, operating system, m...

The scenarios proposed in this deliverable are intended to identify the multiple dimensions of interoperability, and also foster further discussions with other work packages (WP1 to WP5). These will be refined and extended as the project progresses. The scenarios have been grouped into three computing domains: Ubiquitous computing, Daily life suppo...