Paulo F. Pires

A Service Approach for Architecting Application Independent Wireless Sensor Networks

The current sensor networks are assumed to be designed for specific applications, having data communication protocols strongly coupled to applications. The future sensor networks are envisioned as comprising heterogeneous devices assisting to a large range of applications. To achieve this goal, a new architecture approach is needed, having application specific features separated from the data communication protocol, while influencing its behavior. We propose a Web Services approach for the design of sensor network, in which sensor nodes are service providers and applications are clients of such services. Our main goal is to enable a flexible architecture in which sensor networks data can be accessed by users spread all over the world.

On the interplay of Internet of Things and Cloud Computing

The Internet of Things (IoT) is a novel paradigm relying on the interaction of smart objects (things) with each other and with physical and/or virtual resources through the Internet. Despite the recent advances that have made IoT a reality, there are several challenges to be addressed towards exploiting its full potential and promoting tangible benefits to society, environment, economy, and individual citizens. Recently, Cloud Computing has been advocated as a promising approach to tackle some of the existing challenges in IoT while leveraging its adoption and bringing new opportunities. With the combination of IoT and Cloud Computing, the cloud becomes an intermediate layer between smart objects and applications that make use of data and resources provided by these objects. On the one hand, IoT can benefit from the almost unlimited resources of Cloud Computing to implement management and composition of services related to smart objects and their provided data. On the other hand, the cloud can benefit from IoT by broadening its operation scope to deal with real-world objects. In spite of this synergy, the literature still lacks of a broad, comprehensive overview on what has been investigated on the integration of IoT and Cloud Computing and what are the open issues to be addressed in future research and development. The goal of this work is to fill this gap by systematically collecting and analyzing studies available in the literature aiming to: (i) obtain a comprehensive understanding on the integration of IoT and Cloud Computing paradigms; (ii) provide an overview of the current state of research on this topic; and (iii) identify important gaps in the existing approaches as well as promising research directions. To achieve this goal, a systematic mapping study was performed covering papers recently published in journals, conferences, and workshops, available at five relevant electronic databases. As a result, 35 studies were selected presenting strategies and solutions on how to integrate IoT and Cloud Computing as well as scenarios, research challenges, and opportunities in this context. Besides confirming the increasing interest on the integration of IoT and Cloud Computing, this paper reports the main outcomes of the performed systematic mapping by both presenting an overview of the state of the art on the investigated topic and shedding light on important challenges and potential directions to future research.

Efficient allocation of resources in multiple heterogeneous Wireless Sensor Networks

Wireless Sensor Networks (WSNs) are useful for a wide range of applications, from different domains. Recently, new features and design trends have emerged in the WSN field, making those networks appealing not only to the scientific community but also to the industry. One such trend is the running different applications on heterogeneous sensor nodes deployed in multiple WSNs in order to better exploit the expensive physical network infrastructure. Another trend deals with the capability of accessing sensor generated data from the Web, fitting WSNs in novel paradigms of Internet of Things (IoT) and Web of Things (WoT). Using well-known and broadly accepted Web standards and protocols enables the interoperation of heterogeneous WSNs and the integration of their data with other Web resources, in order to provide the final user with value-added information and applications. Such emergent scenarios where multiple networks and applications interoperate to meet high level requirements of the user will pose several changes in the design and execution of WSN systems. One of these challenges regards the fact that applications will probably compete for the resources offered by the underlying sensor nodes through the Web. Thus, it is crucial to design mechanisms that effectively and dynamically coordinate the sharing of the available resources to optimize resource utilization while meeting application requirements. However, it is likely that Quality of Service (QoS) requirements of different applications cannot be simultaneously met, while efficiently sharing the scarce networks resources, thus bringing the need of managing an inherent tradeoff. In this paper, we argue that a middleware platform is required to manage heterogeneous WSNs and efficiently share their resources while satisfying user needs in the emergent scenarios of WoT. Such middleware should provide several services to control running application as well as to distribute and coordinate nodes in the execution of submitted sensing tasks in an energy-efficient and QoS-enabled way. As part of the middleware provided services we present the Resource Allocation in Heterogeneous WSNs (SACHSEN) algorithm. SACHSEN is a new resource allocation heuristic for systems composed of heterogeneous WSNs that effectively deals with the tradeoff between possibly conflicting QoS requirements and exploits heterogeneity of multiple WSNs. The proposed algorithm is designed to effectively exploit the heterogeneity of WSNs.The proposed algorithm is designed to enable running multiple applications simultaneously.SACHSEN is implemented as a functional component of an existent middleware.

Monitoring e-business Web services usage through a log based architecture

The emergence of Web services represents a significant advance in the continuing evolution of e-business. In order to fully explore business opportunities provided by this paradigm, it is important to track its utilization. This can be done through the use of logging facilities. However, current Web logging approaches do not contemplate Web services utilization. This paper presents a Web services logging architecture based on SOAP intermediaries that captures comprehensive services usage information, which can be explored to improve B2B and B2C transactions by providing feedback on customer electronic behavior.

Managing structural genomic workflows using web services

In silico scientific experiments encompass multiple combinations of program and data resources. Each resource combination in an execution flow is called a scientific workflow. In bioinformatics environments, program composition is a frequent operation, requiring complex management. A scientist faces many challenges when building an experiment: finding the right program to use, the adequate parameters to tune, managing input/output data, building and reusing workflows. Typically, these workflows are implemented using script languages because of their simplicity, despite their specificity and difficulty of reuse. In contrast, Web service technology was specially conceived to encapsulate and combine programs and data, providing interoperation between applications from different platforms. The Web services approach is superior to scripts with regard to interoperability, scalability and flexibility issues. We have combined metadata support with Web services within a framework that supports scientific workflows. While most works are focused on metadata issues to manage and integrate heterogeneous scientific data sources, in this work we concentrate on metadata support to program management within workflows. We have used this framework with a real structural genomic workflow, showing its viability and evidencing its advantages.

Reflective middleware for wireless sensor networks

Wireless Sensor Networks (WSNs) are distributed systems whose main goal is to collect and deliver data to applications. This paper proposes a reflective, service-oriented middleware for WSN. The middleware provides an abstraction layer between applications and the underlying network infrastructure and it also keeps the balance between application QoS requirements and the network lifetime. It monitors both network and application execution states, performing a network adaptation whenever it is needed. Simulation results show that the network residual energy can be increased in more than 100% when adopting an adaptation strategy, while the application QoS requirement is respected.

Automatic composition of Web services with contingency plans

The semantic Web technology and the Web services description language extensibility may be combined to describe services in an unambiguous and machine interpretable way, automating Web services discovery, selection and invocation. In this paper, we present an algorithm and a prototype for the automatic composition of Web services that implement workflows described in a high level language. Our approach has many advantages comparing to the manual creation of a simple program composition, such as smaller implementation time and cost, reliability with the generation of contingency plans, greater capacity to evolve with the dynamic service discovery, and faster execution time with the use of heuristics. We use the OWLS ontology to semantically describe Web services metadata and indexes to help selecting them. The proposed algorithm considers that equivalent services may have different interfaces and also respects preferences of the users.

GARSA: genomic analysis resources for sequence annotation

SUMMARY Growth of genome data and analysis possibilities have brought new levels of difficulty for scientists to understand, integrate and deal with all this ever-increasing information. In this scenario, GARSA has been conceived aiming to facilitate the tasks of integrating, analyzing and presenting genomic information from several bioinformatics tools and genomic databases, in a flexible way. GARSA is a user-friendly web-based system designed to analyze genomic data in the context of a pipeline. EST and GGS data can be analyzed using the system since it accepts (1) chromatograms, (2) download of sequences from GenBank, (3) Fasta files stored locally or (4) a combination of all three. Quality evaluation of chromatograms, vector removing and clusterization are easily performed as part of the pipeline. A number of local and customizable Blast and CDD analyses can be performed as well as Interpro, complemented with phylogeny analyses. GARSA is being used for the analyses of Trypanosoma vivax (GSS and EST), Trypanosoma rangeli (GSS, EST and ORESTES), Bothrops jararaca (EST), Piaractus mesopotamicus (EST) and Lutzomyia longipalpis (EST). AVAILABILITY The GARSA system is freely available under GPL license (http://www.biowebdb.org/garsa/). For download requests visit http://www.biowebdb.org/garsa/ or contact Dr Alberto Dávila.

A flexible middleware system for wireless sensor networks

The current wireless sensor networks (WSN) are assumed to be designed for specific applications, having data communication protocols strongly coupled to applications. The future WSNs are envisioned as comprising of heterogeneous devices assisting to a large range of applications. To achieve this goal, a flexible middleware layer is needed, separating application specific features from the data communication protocol, while allowing applications to influence the WSN behavior for energy efficiency. We propose a service-based middleware system for WSNs. In our proposal, sensor nodes are service providers and applications are clients of such services. Our main goal is to enable an interoperability layer among applications and sensor networks, among different sensors in a WSN and eventually among different WSN spread all over the world.

Building Reliable Web Services Compositions

The recent evolution of internet technologies, mainly guided by the Extensible Markup Language (XML) and its related technologies, are extending the role of the World Wide Web from information interaction to service interaction. This next wave of the internet era is being driven by a concept named Web services. The Web services technology provides the underpinning to a new business opportunity, i.e., the possibility of providing value-added Web services. However, the building of value-added services on this new environment is not a trivial task. Due to the many singularities of the Web service environment, such as the inherent structural and behavioral heterogeneity of Web services, as well as their strict autonomy, it is not possible to rely on the current models and solutions to build and coordinate compositions of Web services. In this paper, we present a framework for building reliable Web service compositions on top of heterogeneous and autonomous Web services.