Abstract: This work addresses networked embedded systems enabling the seam-
less interconnection of smart building automations to the Internet and
their abstractions as web services. In our approach, such abstractions are
used to primarily create a exible, holistic and scalable system and allow
external end-users to compose and run their own smart/green building
automation application services on top of this system.
Towards this direction, in this paper we present a smart building test-
bed consisting of several sensor motes and spanning across seven rooms.
Our test-bed's design and implementation simultaneously addresses sev-
eral corresponding system layers; from hardware interfaces, embedded
IPv6 networking and energy balancing routing algorithms to a RESTful
architecture and over the web development of sophisticated, smart, green
scenarios. In fact, we showcase how IPv6 embedded networking combined
with RESTful architectures make the creation of building automation ap-
plications as easy as creating any other Internet Web Service.
Abstract: In this work we present the architecture and implementation of WebDust, a software platform for managing multiple, heterogeneous (both in terms of software and hardware), geographically disparate sensor networks. We describe in detail the main concepts behind its design, and basic aspects of its implementation, including the services provided to end-users and developers. WebDust uses a peer-to-peer substrate, based on JXTA, in order to unify multiple sensor networks installed in various geographic areas. We aim at providing a software framework that will permit developers to deal with the new and critical aspects that networks of sensors and tiny devices bring into global computing, and to provide a coherent set of high level services, design rules and technical recommendations, in order to be able to develop the envisioned applications of global sensor networks. Furthermore, we give an overview of a deployed distributed testbed, consisting of a total 56 nodes and describing in more detail two specific testbed sites and the integration of the related software and hardware technologies used for its operation with our platform. Finally, we describe the design and implementation of an interface option provided to end-users, based on the popular Google Earth application.
Abstract: Raising awareness among young people and changing their behaviour and habits concerning energy usage is key to achieving sustained energy saving. Additionally, young people are very sensitive to environmental protection so raising awareness among children is much easier than with any other group of citizens. This work examines ways to create an innovative Information & Communication Technologies (ICT) ecosystem (including web-based, mobile, social and sensing elements) tailored specifically for school environments, taking into account both the users (faculty, staff, students, parents) and school buildings, thus motivating and supporting young citizens¢ behavioural change to achieve greater energy efficiency. A mixture of open-source IoT hardware and proprietary platforms on the infrastructure level, are currently being utilized for monitoring a fleet of 18 educational buildings across 3 countries, comprising over 700 IoT monitoring points. Hereon presented is the system¢s high-level architecture, as well as several aspects of its implementation, related to the application domain of educational building monitoring and energy efficiency. The system is developed based on open-source technologies and services in order to make it capable of providing open IT-infrastructure and support from different commercial hardware/sensor vendors as well as open-source solutions. The system presented can be used to develop and offer new app-based solutions that can be used either for educational purposes or for managing the energy efficiency of the building. The system is replicable and adaptable to settings that may be different than the scenarios envisioned here (e.g., targeting different climate zones), different IT infrastructures and can be easily extended to accommodate integration with other systems. The overall performance of the system is evaluated in real-world environment in terms of scalability, responsiveness and simplicity.
Abstract: We present the conceptual basis and the initial planning for an open source management architecture for wireless sensor networks (WSN). Although there is an abundance of open source tools serving the administrative needs of WSN deployments, there is a lack of tools or platforms for high level integrated WSN management. This is because of a variety of factors, including the lack of open source management tools, the immaturity of tools that offer manageability for WSNs, the limited high level management capabilities of sensor devices and architectures, and the lack of standardization. The current work is, to our knowledge, the first effort to conceptualize, formalize and design a remote, integrated management platform for the support of WSN research laboratories. The platform is based on the integration and extension of two innovative platforms: jWebDust, a WSN operation and management platform, and OpenRSM, an open source integrated remote systems and network management platform. The proposed system architecture can support several levels of integration (infrastructure management, functionality integration, firmware management), corresponding to different use-cases and application settings.
Abstract: Wireless sensor networks are a recently introduced category of ad hoc computer networks, which are comprised by nodes of small size and limited computing and energy resources. Such nodes are able of measuring physical properties such as temperature, humidity, etc., wireless communication between each other and in some cases interaction with their surrounding environments (through the use of electromechanical parts).
As these networks have begun to be widely available (in terms of cost and commercial hardware availability), their field of application and philosophy of use is constantly evolving. We have numerous examples of their applications, ranging from monitoring the biodiversity of a specific outdoor area to structural health monitoring of bridges, and also networks ranging from few tens of nodes to even thousands of nodes.
In this PhD thesis we investigated the following basic research lines related to wireless sensor networks:
a) their simulation,
b) the development of data propagation protocols suited to such networks and their evaluation through simulation,
c) the modelling of ``hostile'' circumstances (obstacles) during their operation and evaluation of their impact through simulation,
d) the development of a sensor network management application.
Regarding simulation, we initially placed an emphasis to issues such as the effective simulation of networks of several thousands of nodes, and in that respect we developed a network simulator (simDust), which is extendable through the addition of new data propagation protocols and visualization capabilities. This simulator was used to evaluate the performance of a number of characteristic data propagation protocols for wireless sensor networks. Furthermore, we developed a new protocol (VRTP) and evaluated its performance against other similar protocols. Our studies show that the new protocol, that uses dynamic changes of the transmission range of the network nodes, performs better in certain cases than other related protocols, especially in networks containing obstacles and in the case of non-homogeneous placement of nodes.
Moreover, we emphasized on the addition of ``realistic'' conditions to the simulation of such protocols, that have an adversarial effect on their operation. Our goal was to introduce a model for obstacles that adds little computational overhead to a simulator, and also study the effect of the inclusion of such a model on data propagation protocols that use geographic information (absolute or relative). Such protocols are relatively sensitive to dynamic topology changes and network conditions. Through our experiments, we show that the inclusion of obstacles during simulation can have a significant effect on these protocols.
Finally, regarding applications, we initially proposed an architecture (WebDust/ShareSense), for the management of such networks, that would provide basic capabilities of managing such networks and developing applications above it. Features that set it apart are the capability of managing multiple heterogeneous sensor networks, openess, the use of a peer-to-peer architecture for the interconnection of multiple sensor network. A large part of the proposed architecture was implemented, while the overall architecture was extended to also include additional visualization capabilities.
Abstract: Fun in Numbers (FinN) is a platform for developing and playing mobile, locative and collaborative distributed games
using wireless sensors. Using FinN, a very large and diverse set of games can be enhanced, by maximizing the on-game
experience and collecting statistics for off-line, web-based view. At the same time the essence of such games remains the
same: fun in large numbers, in every place and at any time. FinN is implemented using a combination of JAVA Standard
and Mobile editions, while on the hardware part we use wireless sensor devices, called Sun SPOTs. In the future, mobile
phones that have some kind of sensors embedded, or other custom devices can be used for the same purpose. We report a
number of examples of games created with FinN and briefly present the architecture of our platform.
Abstract: Educational buildings constitute 17% of the non-residential building stock in the EU , while recent work shows that a focus on energy use in schools can potentially yield an array of rewards, in concert with educational excellence and a healthy learning environment .
Having these in mind, GAIA1, a Horizon2020 EC-funded project, is developing an IoT platform
that combines sensing, web-based and gamification elements, in order to address the
educational community. Its primary aim is to increase awareness about energy consumption
and sustainability, based on real sensor data produced by the school buildings where students and teachers live and work, while also lead towards behavior change in terms of energy efficiency.
Abstract: Wireless sensor networks can be very useful in applications that require the detection of crucial events, in physical environments subjected to critical conditions, and the propagation of data reporting their realization to a control center. In this paper we propose jWebDust, a generic and modular application environment for developing and managing applications that are based on wireless sensor networks. Our software architecture provides a range of services that allow to create customized applications with minimum implementation effort that are easy to administrate. We move beyond the ?networking-centric? view of sensor network research and focus on how the end user (administrator, control center supervisor, etc.) will visualize and interact with the system.
We here present its open architecture, the most important design decisions, and discuss its distinct features and functionalities. jWebDust allows heterogeneous components to interoperate (real world sensor networks will rarely be homogeneous) and allows the integrated management and control of multiple such networks by also defining web-based mechanisms to visualize the network state, the results of queries, and a means to inject queries in the network. The architecture also illustrates how existing protocols for various services can interoperate in a bigger framework - such as the tree construction, query routing, etc.
Abstract: In this paper we present the design of jWebDust, a generic and modular application environment for developing and managing applications based on wireless sensor networks that are accessible via the internet. Our software architecture provides a range of services that allow to create customized web-based applications with minimum implementation effort that are easy to administrate. We here present its open architecture, the most important design decisions, and discuss its distinct features and functionalities. jWebDust allows heterogeneous components to interoperate and the integrated management and control of multiple such networks by defining web-based mechanisms to visualize the network state, the results of queries, and a means to inject queries in the network.
Abstract: In this work we present the design of jWebDust, a
software environment for monitoring and controlling sensor networks via a web interface. Our software architecture provides a range of services that allow to create customized applications with minimum implementation effort that are easy to administrate. We present its open architecture, the most important design decisions, and discuss its distinct features and functionalities. jWebDust will allow heterogeneous components to operate in the same sensor network, and the integrated management and control of multiple such networks by defining web-based mechanisms to visualize the network state, the results of queries, and a means to inject queries in the network.
Abstract: We present the conceptual basis and the initial planning for an open
source management architecture for wireless sensor networks (WSN). Although
there is an abundance of open source tools serving the administrative needs of
WSN deployments, there is a lack of tools or platforms for high level integrated
WSN management. The current work is, to our knowledge, the first effort to
conceptualize and design a remote, integrated management platform for the
support of WSN research laboratories. The platform is based on the integration
and extension of two innovative platforms: jWebDust, a WSN operation and
management platform, and OpenRSM, an open source integrated remote
systems and network management platform. The proposed system architecture
can support several levels of integration in order to cover to multiple,
qualitatively differentiated use-cases.
Abstract: In this paper, we discuss the integration of Wireless
Sensor Networks (WSN) and smart objects with the Web. We present a set of research challenges which we believe are the most important ones rising from this integration and propose a prototype system, Uberdust, which addresses such challenges. Uberdust is a brokerage web service for connecting smart objects to the Internet of Things, providing storage, sharing and discovery of real-time and historical data from smart objects, devices & building installations around the world via the Web. Our system provides high-level language-independent APIs so IoT application developers may choose their favorite programming or scripting languages.
Abstract: For the Internet of Things to ﬁnally become a reality, obstacles on different levels need to be overcome. This is especially true for the upcoming challenge of leaving the domain of technical experts and scientists. Devices need to connect to the Internet and be able to offer services. They have to announce and describe these services in machine understandable ways so that user-facing systems are able to ﬁnd and utilize them. They have to learn about their physical surroundings, so that they can serve sensing or acting purposes without explicit conﬁguration or programming. Finally, it must be possible to include IoT devices in complex systems that combine local and remote data, from different sources, in novel and surprising ways.
We show how all of that is possible today. Our solution uses open standards and state-of-the art protocols to achieve this. It is based on 6LowPAN and CoAP for the communications part, semantic web technologies for meaningful data exchange, autonomous sensor correlation to learn about the environment, and software built around the Linked Data principles to be open for novel and unforeseen applications.
Abstract: We present the basic concepts behind the design and implementation of WebDust, a peer-to-peer platform for organizing,
monitoring and controlling wireless sensor networks, along with a discussion of its application regarding an actual testbed.
Our software architecture provides a range of services that allow to create customized applications with relatively low
implementation overhead. WebDust aims to allow heterogeneous components to operate in the same sensor network, and
give the ability to manage and control large numbers of such networks, possibly on a global scale. We also give insight to
several applications that can be implemented using our platform, and a description of our current testbed.
Abstract: There exists a great amount of algorithms for wireless sensor networks (WSNs) that have never been tried in practice. This is due to the fact that programming sensor nodes still happens on a very technical level. We remedy the situation by introducing our algorithm library Wiselib, which allows for simple implementations of algorithms. It can adopt to a large variety of hardware and software. This is achieved by employing advanced C++ techniques such as templates and inline functions, which allow to write generic code that is resolved and bound at compile time, resulting in virtually no memory or computation overhead at run time. The Wiselib runs on different host operating systems such as Contiki, iSense OS, and ScatterWeb. Furthermore, it runs on virtual nodes simulated by Shawn. The Wiselib provides an algorithm with data structures that suit the specific properties of the target platform. Algorithm code does not contain any platform-specific specializations, allowing a single implementation to run natively on heterogeneous networks. In this paper, we describe the building blocks of the Wiselib, analyze the overhead, and show how cryptographically secured routing algorithms can be implemented. We also report on results from experiments with real sensor node hardware.