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Wireless Metropolitan Area Networks based on IEEE 802.16d/e standards are soon to be deployed in several countries. However, there is lack of published literature with results from actual testbeds. This paper introduces the work done in the EU Sixth Framework Programme Project WEIRD to design and set up WiMAX testbeds in four EU countries. We describe the methodlogy followed, detail our implementation and present results from the testbeds, as deployed in the first phase of WEIRD. The testbeds are used to demonstrate how WiMAX technology can be used to extend the connectivity of the panEuropean data communications network (GEANT2) to isolated and impervious areas and, furthermore, to assure end-to-end quality of service to novel applications.

Choosing or switching between heterogeneous networks according to the highest performance in terms of quality of service is largely inefficient in vertical handover. In fact a service may have unstable performance and require highly frequent vertical handover procedures. In this paper we consider the impact of statistical fluctuations of performance parameters (decision under risk) and propose a soft algorithm that exploits the statistical knowledge in order to reduce outage probability

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IEEE 802.16 networks provide mechanisms for QoS support at MAC level, but end-to-end QoS issues are not addressed in detail in the standards. This paper presents an analysis and an experimental validation of a comprehensive solution that describes and implements end-to-end QoS in networks with IEEE802.16e segments. A complete QoS model has been specified, defining the traffic descriptors, the QoS parameters and the resource management functions for networks with WiMAX access. This QoS model has been applied to the Next Step in Signalling (NSIS) protocol suite and its impact has been evaluated on end-to-end QoS when heterogeneous network domains are involved. This work is based on the of results of activities focussed on the study of signalling protocols, carried out within the EU Integrated Project WEIRD (WiMAX Extension to Isolated Research Data networks).

In the present paper the authors show how the application of Semantic Web technologies, i.e. ontology and rule languages, can be used to describe situations and enhance situation awareness providing also suggested actions to the human operator in a data fusion architecture aimed at airport security. The paper presents the ontology design, i.e. main classes and relationship, and the possible roles for situation categorization including the application of rules. In addition, an insight of alternative options including their pros and cons in terms of representation expressivity and complexity, is provided. An analysis of the architectural issues and their impacts considering available technologies and their limitations have been included in the present paper. In order to validate the proposed approach both from the representation and from the complexity point of view, a comparison with a well-established framework, i.e. Situation Ontology developed by Vistology, has been carried out in terms of language complexity and dynamic behaviour in order to assess the performance and limits of the proposed system. © 2014 IEEE

In this article we propose strategies for optimization of vertical handover among broadcast networks. The specific technologies of DVB-H and UMTS/MBMS are taken into account for the modelling of technological parameters including energy consumption and frame loss. Energy consumption is important in a mobile context in order to maximize the possible service duration while frame loss must be considered in order to provide services with an acceptable quality of experience. The proposed strategies are based on two different functions: a ratio between the energy consumption and the frame loss along and a linear objective function. The two function are compared with functions based on only one parameter and against the theoretic frame loss and energy consumption. The paper gives numerical results obtained through simulations in different mobility conditions in order to assess the performance of the proposed functions in terms of frame loss and energy consumption as well as in frequency of vertical handovers