Bringing context-aware access to the web through spoken interaction

The web has become the largest repository of multimedia information and its convergence with telecommunications is now bringing the benefits of web technology to hand-held devices. To optimize data access using these devices and provide services which meet the user needs through intelligent information retrieval, the system must sense and interpret the user environment and the communication context. In addition, natural spoken conversation with handheld devices makes possible the use of these applications in environments in which the use of GUI interfaces is not effective, provides a more natural human-computer interaction, and facilitates access to the web for people with visual or motor disabilities, allowing their integration and the elimination of barriers to Internet access. In this paper, we present an architecture for the design of context-aware systems that use speech to access web services. Our contribution focuses specifically on the use of context information to improve the effectiveness of providing web services by using a spoken dialog system for the user-system interaction. We also describe an application of our proposal to develop a context-aware railway information system, and provide a detailed evaluation of the influence of the context information in the quality of the services that are supplied.Research funded by projects CICYT TIN2011-28620-C02-01, CICYT TEC 2011-28626-C02-02, CAM CONTEXTS (S2009/TIC-1485), and DPS2008-07029-C02-02.Publicad

Initial Architectural Style for CHOReOS Choreographies (D1.3)

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 awareness & adaptability. This deliverable then revisits the traditional definitions of service-oriented component (i.e., service), connector (interaction protocol and related service bus for interop- erability) and configuration (system-wide architecture composing services according to orchestration or more general choreography patterns) to meet the FI challenges. Specifically, CHOReOS components enable lever- aging the diversity of Web-based services that integrate in the FI (i.e., WS∗ and RESTful web-based services, and from business to thing-based services) as well as the ultra large service base envisioned for the FI. As for CHOReOS connectors, they bring together the highly heterogeneous interaction paradigms that are now used in today's increasingly complex distributed systems and further support interoperability across heterogeneous paradigms. Finally, CHOReOS coordination protocols foster choreography-based coordination for the sake of scalability, while preventing undesired behavior (i.e., undesired service interactions that would violate the specified choreography). A key aspect of the proposed CHOReOS architectural style is to introduce novel ab- stractions for all its elements, which enable leveraging the wide diversity of the FI, in all the dimensions of scale, heterogeneity and mobility. The CHOReOS style further sets the base ground for the development (from design to implementation) of the CHOReOS Integrated Development and Runtime Environment, and especially for the specification and design of choreography-based systems (studied in WP2 complemented with WP4 work on Governance and V&V) and the development of the CHOReOS service-oriented middleware (studied in WP3)

Participant Domain Name Token Profile for security enhancements supporting service oriented architecture

This research proposes a new secure token profile for improving the existing Web Services security standards. It provides a new authentication mechanism. This additional level of security is important for the Service-Oriented Architecture (SOA), which is an architectural style that uses a set of principles and design rules to shape interacting applications and maintain interoperability. Currently, the market push is towards SOA, which provides several advantages, for instance: integration with heterogeneous systems, services reuse, standardization of data exchange, etc. Web Services is one of the technologies to implement SOA and it can be implemented using Simple Object Access Protocol (SOAP). A SOAP-based Web Service relies on XML for its message format and common application layer protocols for message negotiation and transmission. However, it is a security challenge when a message is transmitted over the network, especially on the Internet. The Organization for Advancement of Structured Information Standards (OASIS) announced a set of Web Services Security standards that focus on two major areas. “Who” can use the Web Service and “What” are the permissions. However, the location or domain of the message sender is not authenticated. Therefore, a new secure token profile called: Participant Domain Name Token Profile (PDNT) is created to tackle this issue. The PDNT provides a new security feature, which the existing token profiles do not address. Location-based authentication is achieved if adopting the PDNT when using Web Services. In the performance evaluation, PDNT is demonstrated to be significantly faster than other secure token profiles. The processing overhead of using the PDNT with other secure token profiles is very small given the additional security provided. Therefore all the participants can acquire the benefits of increased security and performance at low cost

Integration of Event Processing with Service-oriented Architectures and Business Processes

Data sources like the Internet of Things or Cyber-physical Systems provide enormous amounts of real-time information in form of streams of events. The use of such event streams enables reactive software components as building blocks in a new generation of systems. Businesses, for example, can benefit from the integration of event streams; new services can be provided to customers, or existing business processes can be improved. The development of reactive systems and the integration with existing application landscapes, however, is challenging. While traditional system components follow a pull-based request/reply interaction style, event-based systems follow a push-based interaction scheme; events arrive continuously and application logic is triggered implicitly. To benefit from push-based and pull-based interactions together, an intuitive software abstraction is necessary to integrate push-based application logic with existing systems. In this work we introduce such an abstraction: we present Event Stream Processing Units (SPUs) - a container model for the encapsulation of event-processing application logic at the technical layer as well as at the business process layer. At the technical layer SPUs provide a service-like abstraction and simplify the development of scalable reactive applications. At the business process layer SPUs make event processing explicitly representable. SPUs have a managed lifecycle and are instantiated implicitly - upon arrival of appropriate events - or explicitly upon request. At the business process layer SPUs encapsulate application logic for event stream processing and enable a seamless transition between process models, executable process representations, and components at the IT layer. Throughout this work, we focus on different aspects of the SPU container model: we first introduce the SPU container model and its execution semantics. Since SPUs rely on a publish/subscribe system for event dissemination, we discuss quality of service requirements in the context of event processing. SPUs rely on input in form of events; in event-based systems, however, event production is logically decoupled, i.e., event producers are not aware of the event consumers. This influences the system development process and requires an appropriate methodology. Fur this purpose we present a requirements engineering approach that takes the specifics of event-based applications into account. The integration of events with business processes leads to new business opportunities. SPUs can encapsulate event processing at the abstraction level of business functions and enable a seamless integration with business processes. For this integration, we introduce extensions to the business process modeling notations BPMN and EPCs to model SPUs. We also present a model-to-execute workflow for SPU-containing process models and implementation with business process modeling software. The SPU container model itself is language-agnostic; thus, we present Eventlets as SPU implementation based on Java Enterprise technology. Eventlets are executed inside a distributed middleware and follow a lifecycle. They reduce the development effort of scalable event processing applications as we show in our evaluation. Since the SPU container model introduces an additional layer of abstraction we analyze the overhead in terms of performance and show that Eventlets can compete with traditional event processing approaches in terms of performance. SPUs can be used to process sensitive data, e.g., in health care environments. Thus, privacy protection is an important requirement for certain use cases and we sketch the application of a privacy-preserving event dissemination scheme to protect event consumers and producers from curious brokers. We also quantify the resulting overhead introduced by a privacy-preserving brokering scheme in an evaluation