Alessandra Toninelli

Semantic-based discovery to support mobile context-aware service access

The increasing diffusion of portable devices with wireless connectivity enables new pervasive scenarios, where users require tailored service access according to their needs, position, and execution/environment conditions (context-aware services). A crucial requirement for the context-aware service provisioning is the dynamic retrieval and interaction with local resources, i.e., resource discovery. The high degree of dynamicity and heterogeneity of mobile environments requires to rethink and/or extend traditional discovery solutions to support more intelligent service search and retrieval, personalized to user context conditions. Several research efforts have recently emerged in the field of service discovery that, based on semantic data representation and technologies, allow flexible matching between user requirements and service capabilities in open and dynamic deployment scenarios. This paper proposes a middleware-level approach to support user-centric semantic service discovery. The presented middleware, called AIDAS, exploits context-awareness based on user/device/service profile metadata to provide personalized views on services of interest, and supports semantic-based matchmaking between requested and offered service capabilities. In addition, AIDAS addresses the crucial management issue of providing resource-constrained portable devices with needed semantic support features. Semantic support services, such as ontology repositories and inference engines, typically require a large amount of computational and memory resources that might not fit the properties of all mobile devices. AIDAS addresses this issue by transparently and dynamically adapting semantic-based discovery support to the properties of different access devices.

Context-aware semantic discovery for next generation mobile systems

A mass market of users with differentiated preferences and heterogeneous wireless terminals will increasingly access services dynamically introduced by competitor providers. In next-generation mobile systems, novel solutions for user-centric service discovery are crucial to provide personalized views of only the services of potential interest. The service view personalization should be based on user context, for example, user preferences, access device capabilities, and environment conditions, and should exploit semantic technologies to allow flexible matching between requirements and capabilities in open and dynamic deployment scenarios. Our MIDAS middleware exemplifies how to exploit context awareness based on user/device/service profile metadata and semantic-based matchmaking

Enabling secure service discovery in mobile healthcare enterprise networks

Advances in wireless networks, sensors, and portable devices offer unique chances to deliver novel anytime anywhere medical services and information, thus enabling a wide range of healthcare applications, from mobile telemedicine to remote patient monitoring, from location-based medical services to emergency response. Mobile e-health has great potential to extend enterprise hospital services beyond traditional boundaries, but faces many organizational and technological challenges. In pervasive healthcare environments, characterized by user/service mobility, device heterogeneity, and wide deployment scale, a crucial issue is to discover available healthcare services taking into account the dynamic operational and environmental context of patient-healthcare operator interactions. In particular, novel discovery solutions should support interoperability in healthcare service descriptions and ensure security during the discovery process by making services discoverable by authorized users only. This article proposes a semantic-based secure discovery framework for mobile healthcare enterprise networks that exploits semantic metadata (profiles and policies) to allow flexible and secure service search/retrieval. As a key feature, our approach integrates access control functionalities within the discovery framework to provide users with filtered views on available services based on service access requirements and user security credentials.

Proteus: A Semantic Context-Aware Adaptive Policy Model

The growing diffusion of portable devices enables users to benefit from anytime and anywhere impromptu collaboration. Appropriate policy models that take into account the dynamicity and heterogeneity of the new pervasive collaboration scenario are crucial to ensure secure sharing of information. Collaborating entities cannot be predetermined and resource availability frequently varies, even unpredictably, due to user/device mobility, thus complicating resource access control. Policies cannot be defined based on entitys identities/roles, as in traditional security solutions, or be specified a priori to face any operative run-time condition, and require continuous adjustments to adapt to the current situation. To address these issues this paper advocates the adoption of a semantic context-aware paradigm to policy specification. Context- awareness allows operations on resources to be controlled based on context visibility whereas semantic technologies allow the high-level description and reasoning about context/policies. The paper describes Proteus that, as a key feature, combines these two design guidelines to enable dynamic adaptation of policies depending on context changes. In particular, the paper shows how ontologies and logic programming rules can be used to leverage policy adaptation.

Supporting context awareness in smart environments: a scalable approach to information interoperability

A still open issue in pervasive systems is how to effectively support the development and run-time execution of smart applications in wide-scale and open deployment scenarios. That calls for i) easy and low-cost interoperability with legacy systems/services and ii) scalability in terms of both overhead and performance results for different classes of applications with different quality requirements. In this position paper, we report the research work we are doing within an ongoing project on the exploitation of context awareness for scalability in smart environments, where interoperability is achieved at the information level via semantic technologies. In particular, the paper shows how context-aware middleware facilities can help in dynamically determining personalized views on a shared information space, implemented as coordinated repositories of Resource Description Format triples. The advantages are relevant in terms of usability (automatic discarding of unsuitable resource/service components) and overhead reduction (limitation of quality monitoring space).

Smart applications for the maintenance of large buildings: How to achieve ontology-based interoperability at the information level

Industrial applications for smart environments call for techniques and methodologies to improve interoperability, reusability, and easy integration with existing applications, thus reducing development costs and time-to-market. This paper presents a novel and practical approach to smart context-aware applications for the maintenance of large buildings, where ontology-based interoperability is exploited to enable the easy integration of multivendor multiplatform devices/sensors with existing applications. The proposed solution has been designed and implemented on top of the smart environment architecture developed within the SOFIA project. In particular, the paper shows how it is possible to realize a set of context-aware smart maintenance applications capable of monitoring environmental variables, automatically detecting building-related faults, and promptly calling for specific interventions in a multi-modal way, always by carefully considering cross-industry interoperability.

A context-centric security middleware for service provisioning in pervasive computing

Pervasive user mobility, wireless connectivity and the widespread diffusion of portable devices raise new challenges for ubiquitous service provisioning. An emerging architecture solution in the wireless Internet is based on mobile proxies (implemented as mobile agent-based middleware components) over the fixed network that follow the movements and act on behalf of the limited wireless clients. It is crucial that mobile proxies have full visibility of their context, i.e., the set of available and relevant resources, depending on access control rules, client location, user preferences, privacy requirements, terminal characteristics, and current state of hosting environments. The paper presents the design and implementation of a context-centric security middleware, called UbiCOSM, for MA-based service provisioning in pervasive computing. UbiCOSM dynamically determines the contexts of mobile proxies, and effectively rules the access to them, by taking into account different types of metadata (user profiles and authorization policies), expressed at a high level of abstraction and cleanly separated from the service logic. The paper also shows the functioning of UbiCOSM in the design and the development of a mobile context-centric airport business assistant.

Middleware Support for Mobile Social Ecosystems

With the increased prevalence of advanced mobile devices (the so-called “smart” phones), interest has grown in mobile social ecosystems, where users not only access traditional Web-based social networks using their mobile devices, but are also able to use the context information provided by these devices to further enrich their interactions. Owing to the large variety of platforms available for smart phones, as well as the different ways that data and context information is represented, it is natural to think of middleware solutions that the developers of these systems can use while creating their applications. In this paper, we highlight the issues which should be addressed by middleware designed for mobile social ecosystems, taking into account the heterogeneity of both deployment nodes and available data, the intrinsic distributed nature of mobile social applications, as well as users’ security concerns. As part of our ongoing effort to develop this middleware, we present a comprehensive model to represent mobile social ecosystems and the interactions possible in them, and show how to exploit it in a representative scenario.

Adaptive Semantic Middleware for Mobile Environments

Context-awareness is considered a key driving principle for the design and provisioning of adaptable pervasive services. Rightfully describing and interpreting context, however, is a challenging issue. Semantic technologies are emerging as effective means to describe and reason about context information and to allow unknown entities to have a common understanding of context. However, the exploitation of semantic technologies for the design/deployment of context-aware applications in pervasive environments replete with heterogeneous devices requires to address several issues. In particular, a crucial aspect is how to support semantic based service provisioning to mobile devices with limited capabilities. Novel solutions are required to transparently and dynamically adapt semantic-based service provisioning to the properties of different access devices. The paper proposes a middleware-level solution approach that exploits the visibility of two kinds of metadata (profiles and policies) to support the configurability of the semantic support functionalities depending on user/device properties, and that offers a wide set of mechanisms for making viable semantic based service provisioning even to resource-constrained portable devices.

Composing Trust Models towards Interoperable Trust Management

Computational trust is a central paradigm in today’s Internet as our modern society is increasingly relying upon online transactions and social networks. This is indeed leading to the introduction of various trust management systems and associated trust models, which are customized according to their target applications. However, the heterogeneity of trust models prevents exploiting the trust knowledge acquired in one context in another context although this would be beneficial for the digital, ever-connected environment. This is such an issue that this paper addresses by introducing an approach to achieve interoperability between heterogeneous trust management systems. Specifically, we define a trust meta-model that allows the rigorous specification of trust models as well as their composition. The resulting composite trust models enable heterogeneous trust management systems to interoperate transparently through mediators.