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Evaluation of Ambient Assisted Living (AAL) systems is particularly challenging due to the complexity of such systems and to the variety of solutions adopted and services offered. This problem is related to the evaluation of pervasive and ubiquitous systems that has been the focus of many researchers in the recent years and that still awaits for solutions. On the other hand, analyzing and comparing AAL solutions is paramount for the assessment of the research results in this area. EvAAL (Evaluating AAL Systems Through Competitive Benchmarking) is a recently established international competition that aims to address this problem in order to let benchmarking and comparison methodologies of AAL systems emerge from experience. This work describes the first EvAAL competition which was devoted to localization and tracking; proposed evaluation criteria, benchmarks, and achieved results are reported.

Owing to the complexity of Ambient Assisted Living (AAL) systems and platforms, the evaluation of AAL solutions is a complex task that will challenge researchers for years to come. However, the analysis and comparison of proposed solutions is paramount to enable us to assess research results in this area. We have thus organized an international contest called EvAAL: Evaluating AAL Systems Through Competitive Benchmarking. Its aims are to raise interest within the research and developer communities in the multidisciplinary research fields enabling AAL, and to create benchmarks for the evaluation and comparison of AAL systems.

The ZigBee standard defines a service-oriented framework for the implementation of Wireless Sensor Networks (WSNs). In the recent years ZigBee has received the attraction of many research studies focused on the design and the implementation of network gateways able to access and to interact with ZigBee sensors from heterogeneous networks. To address the interoperable challenge, this paper presents ZB4OSGi, an OSGi-based ZigBee gateway able to export the ZigBee network services in the OSGi execution environment without requiring any prior knowledge about the ZigBee protocol. ZB4OSGi exploits a 3-layered architecture enabling the access, abstraction and integration of ZigBee devices to different channels like UPnP or SOAP-REST Web Services. The paper faces with a concrete implementation of ZB4OSGi, by highlighting the features with respect to already existing ZigBee gateways.

Short-term synaptic plasticity undergoes important age-dependent changes that have crucial implications during the development of the nervous system. Paired-pulse facilitation is a form of short-term synaptic plasticity by which the response to the second of two temporally-paired stimuli is larger and more reliable than the response to the first stimulus. In this study, a paired-pulse minimal stimulation technique was used to measure the probability and quantal amplitude of synaptic release at hippocampal synapses from 12-16-day-old (young) and 7-9-week-old (adult) rats. In order to assess the contribution of temperature-dependent processes, we carried out experiments at both room temperature and at near physiological temperature. We report here that neither temperature nor maturation affected the low basal evoked release probability and quantal amplitude of release. However, the warmer temperature revealed a unique developmental increase in facilitated evoked release probability and quantal amplitude of release. As a result, although both basal evoked release and facilitated release are rather unreliable in synapses from young animals, the maturation process at near physiological temperature generates a phenotype with unreliable basal evoked release and highly reliable facilitated release.

The presynaptic Ca2+ signal, which triggers vesicle release, disperses to a broadly distributed residual [Ca2+] ([Ca2+](res)) that plays an important role in synaptic plasticity. We have previously reported a slowing in the decay timecourse of [Ca2+](res) during the second of paired pulses. In this study, we investigated the contributions of organelle and plasma membrane Ca2+ flux pathways to the reduction of effectiveness of [Ca2+](res) clearance during short-term plasticity in Schaffer collateral terminals in the CA1 field of the hippocampus. We show that the slowed decay timecourse is mainly the result of a transport-dependent Ca2+ clearance process; that presynaptic caffeine-sensitive Ca2+ stores are not functionally loaded in the unstimulated terminal, but that these stores can effectively take up Ca2+ even during high frequency trains of stimuli; and that a rate limiting step of sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) kinetics following the first pulse is responsible for a large portion of the observed slowing of [Ca2+](res) clearance during the second pulse. We were able to accurately fit our [Ca2+](res) data with a kinetic model based on these observations and this model predicted a reduction in availability of unbound SERCA during paired pulses, but no saturation of Ca2+ buffer in the endoplasmic reticulum.

Received Signal Strength Indicator (RSSI) is not suitable for fine-grained indoor applications because of temporal variations in wireless fading events. This paper presents a simple and robust mechanism to dynamically calibrate the signal propagation model parameters following the wireless channel variations. The proposed method enhances the accuracy of RSSIbased localization techniques without the extensive, accurate and time-consuming human interventions. The contribution of this proposal are consists in the implementation's easiness and its excellent output performance, compared with the commonly static calibration procedures.

The localization methods based on Received Signal Strength Indicator (RSSI) link the RSSI values to the position of the mobile to be located. In the RSSI localization techniques based on propagation models, the accuracy depends on the tuning of the propagation models parameters. In indoor wireless networks, the propagation conditions are hardly predictable due to the dynamic nature of the RSSI, and consequently the parameters of the propagation model may change. In this paper, we present an automatic virtual calibration method of the propagation model that does not require human intervention; therefore, can be periodically performed, following the wireless channel conditions. We also propose a novel RSSI-based localization algorithm that selects the RSSI values according to their strength, and uses a calibrated propagation model to transform these values into distances, in order to estimate the position of the mobile.

This document is about supporting the start up of AALOA, an AAL Open Association. It explains the rationale behind this effort, sketches an initial comparison with similar organisations, examines the problems that we will find on the road and what are the main issues. It is a practical, short guide to the FLOSS (Free/Libre/Open Source Software) communities and introduces the software commodity and coopetition concepts, which are used to justify the needs of a convergence process towards a common shared platform for AAL. These concepts in addition to the AAL market fragmentation are the essence of the call for action expressed from the Manifesto of AALOA, which is reported in the appendix A. This document clarifies also the changes to the initial strategy of universAAL for creating a community of interested developers around its own platform as proposed in Description of Work. AALOA does not represent the specific community of universAAL project. AALOA will be the community of communities and universAAL will be one of those communities working in synergy for preparing the AAL market breakthrough. The document reports about the status of the AALOA community, the current governing board composition, the communication infrastructures and tools activated, and the list of projects already incubated in AALOA. It sketches a very embryonic roadmap for the association and gives an overview on what one should expect from it.

Localization is an essential service in many context-aware applications and in ambient assisted living (AAL). A promising localization approach is based on Wireless Sensor Networks [1]. These solutions estimate the location of the mobile sensors (also called mobiles) with respect to a set of fixed sensors (or anchors) whose position is known. In this work, we consider a range-based localization [2], that exploits measurements of Received Signal Strength Indicator (RSSI). The use of the RSSI does not require any special hardware and it is available in most of the standard wireless devices, and it has received considerable interest in the recent literature [3].

AAL (Ambient Assisted Living) has great potential for positively influencing the lives of many people. But impact so far has been less than hoped, partly due to fragmentation of research efforts and the lack of a standardised approach for developers. To address this, we are forming the AALOA (AAL Open Association), and invite you to join in our efforts.

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Dependable data storage in wireless sensor networks is becoming increasingly important, due to the lack of reliability of the individual sensors. Recently, data centric storage (DCS) has been proposed to manage in network sensed data. DCS reconsiders ideas and techniques successfully proposed in peer to peer systems within the framework of wireless sensor networks. In particular it assume that data are uniquely named and data storage and retrieval is achieved using names instead of sensor nodes addresses. In this paper, we discuss the limitations of previous approaches, and in particular of Geographic Hash Tables (GHT), and introduce DELiGHT, a protocol which provides fine QoS control by the user and ensures even data distribution, also in non uniform sensor networks. The merits of DELiGHT have been evaluated through simulation in uniform and Gaussian distributed sensor networks. The simulation results show that the protocol provides a better load balancing than the previous proposals and that the QoS is ensured without appreciable overhead.

The rapid development of Wireless Sensor Networks (WSN) technologies gave rise to the need for abstraction mecha- nisms that can simplify the data management tasks. Under this respect, the publish/subscribe paradigms play an im- portant role since they can be used to abstract the WSN in terms that are closer to applicative needs. On the other hand, Data Centric Storage systems (DCS) can provide a low-level support to the implementation of publish/subscribe systems in WSN. In this paper we consider different im- plementations of publish/subscribe systems, based either on DCS or basic network primitives and we compare the result- ing approaches in terms of functionalities and performance.

An erasure encoding based on arithmetic residue codes with non-pairwise-prime moduli is introduced. Data are encoded with n residue digits, and can be reconstructed exactly from any subset of at least n-z available digits not bearing errors. Data can also be reconstructed within a small ? from at least n-z available digits bearing small errors, or from at least n-z-2 available digits bearing a single unrestricted error combined with small errors. Integers z and ? are depending on the actual moduli and redundancy, and small errors are those of magnitude not exceeding ?. Encoding and decoding of data requires simple arithmetic computation. The proposed encoding is suitable for application to wireless sensor networks, when data robustness and confidentiality are critical issues. To this purpose, data are independently collected by n replicated sensing nodes, each replica storing a different digit of the encoded data. This produces data dispersal without requiring wireless communication between nodes. Data retrieval tolerates failure of multiple sensor, as well as small errors arising from independent data collection, and unrestricted errors due to failures or intrusions. The proposed encoding reduces memory and energy requirements of nodes, and contributes to strengthened data security and confidentiality.

In the context of ubiquitous and pervasive computing environments, considerable efforts have been done in order to have audiovisual systems and applications converge, especially in home environments where homes can be considered as spaces of convergence, and for nomadic users with advanced mobile devices as points of convergence. The network of excellence INTERMEDIA seeks to progress beyond home and device-centric convergence towards truly user-centric convergence of multimedia, having as its long term vision "The User as the Multimedia Central", i.e. the user as the point at which services (multimedia applications) and the means for interacting with them (devices and interfaces) converge, (see following figure for the depiction of this vision). One of the biggest challenges that we have to face in the deployment of architectures in such environments is related to, on the one hand, with the security and protection of digital contents that interchanged between users of such architectures and on the other hand with the provision to the users with security mechanisms that allow them to perform secure transactions (e.g. authentication, privacy protection, secure data transfer, etc.) in those environments. Moreover intellectual property protection is a mandatory request in modern multimedia environments like the ones that are going to be deployed in the Intermedia context. Today the end-users are equipped with different types of small devices that allow them to be the digital contents creators, thus creating digital content that wish to share with third parties. In most cases, the end-users would like to have mechanisms which would give them the possibility to protect the content which have created and possibly to set their own usage rights over it, thus specifying towards third users how their digital content shall be used. The main objective of this deliverable is to develop integrated network architecture with security and DRM for interconnected home and body area networks, and to specify appropriate interfaces such that the security and DRM solution will function over different operating platforms. Moreover, it shall initiate research for the efficient deployment of security and DRM in embedded systems (with limited resources). Furthermore, our architecture shall incorporate state-of-the-art technologies, methodologies and standardization in the context of security and DRM aspects. We have achieved the pre-mentioned through a series of tasks: task 5.1.1 - Design of an integrated secure network architecture as it will be incorporated into the demonstrators. Specifications of system interfaces in order to integrate security and DRM solutions, according to MPEG-21 standard, in services and applications of the demonstrators; task 5.1.2 - Further utilization of MPEG-21 primitives in the context of security and DRM, like MPEG-21 IPMP Tools in order to integrate DRM solutions in services and applications that target delivery of protected content that resides into the home network of the user by developing architectures with security and DRM as inherent requirements leading to secure solutions that increase the trust placed by content providers on the system; task 5.2.1 - Enrichment of our cryptographic module "iSecFunc", which adheres to the state-of-the-art technologies with more required security functions and implementation of security functionalities in highly constrained embedded platforms; task 5.2.2 - Further development of the DRM client, in order to enhance and enforce the license that accompanies the content. Moreover, the DRM client shall initiate the procedure of digital contents' rendering, if this is allowed by the relevant license; finally, in task 5.3 - Investigation of integration techniques so that the implemented prototype modules will be seamlessly incorporated into the demonstrators and continuous work on algorithms in order to embed authentication information in the video stream.

Information assurance in Critical Infrastructures (CIs) is a problem of great practical interest and a challeng- ing research field. Within this scope we focus on the problem of monitoring of CIs. In particular, we propose a model to max- imize the amount of monitoring-related data that can survive after a portion of the CI suffers a disaster. The proposed model addresses a specific CI-oil pipelines-, and it is built on the hypothesis that the monitoring data are provided by means of wireless sensor networks. In particular, we consider a CI where the sensors are deployed along the pipelines and execute a com- mon monitoring task with a given sampling rate. In order to ensure data availability the sensors replicate the sensed data to their peers. This model poses a few unique challenges, calling for the optimization of competing system parameters. For in- stance, a higher sampling rate would allow, on one hand, a finer- grain analysis of the situation while on the other hand would consume more energy. High volume of data replication would allow a higher chance for data to survive a disaster-hence help- ing in forensics or further disaster prevention-, while it would cost more in both energetic and bandwidth terms. We derive an analytical model for this scenario. This model can be processed to derive the optimal sampling rate that maximizes the amount of information collected by the monitoring infras- tructure, while satisfying the complex and competing system parameters. Further, simulations are performed on both reg- ular (tree-based) and random generated oil pipelines and show the wide applicability of our model, as well as providing a few non-intuitive results on the behaviour of the competing system parameters. Finally, we develop a case study on a real-world oil pipeline. Results support the quality of the proposed model and its flexibility.

We present a novel authentication scheme that leverages satellite link characteristics such as low bit error rate and no packet reordering. Our approach combines watermarking and signature amortization; the computation overhead experienced on receiver sums up to two hash per block of pictures, and only one digital signature verification for the whole received stream. We propose a theoretical approach to evaluate the algorithm effectiveness, and we present simulation results to validate the proposed authentication algorithm.

One of the aims of the SatNEx (Satellite Network of Excellence, http://www.satnex.de) European project is to provide the scientific community that operates on satellite communications with measurement campaign results and evaluation tools, in order to support research activities that investigate problems in satellite communications at different levels of the OSI stack. In fact, the research activities developed in SatNEx address the most relevant aspects of satellite communications, such as channel modulation and coding schemes, access strategies, advanced networking, end-to-end quality of service, transport performance, delay tolerant networks, and new applications. Even if SatNEx is mainly devoted to satellite communications, integration of satellite and terrestrial wireless segments has also been taken into account. This paper presents the results obtained in the specific research activity devoted to trials and testbeds developed during the SatNEx project. The high number of authors of this paper is an indication of the strong collaborative work sustained, the numerous measurement campaigns, and the complexity in developing integrated testbeds.