Delivering services by building and running virtual organisations

Non peer reviewedPostprin

Optimizing for confidence - Costs and opportunities at the frontier between abstraction and reality

Is there a relationship between computing costs and the confidence people place in the behavior of computing systems? What are the tuning knobs one can use to optimize systems for human confidence instead of correctness in purely abstract models? This report explores these questions by reviewing the mechanisms by which people build confidence in the match between the physical world behavior of machines and their abstract intuition of this behavior according to models or programming language semantics. We highlight in particular that a bottom-up approach relies on arbitrary trust in the accuracy of I/O devices, and that there exists clear cost trade-offs in the use of I/O devices in computing systems. We also show various methods which alleviate the need to trust I/O devices arbitrarily and instead build confidence incrementally "from the outside" by considering systems as black box entities. We highlight cases where these approaches can reach a given confidence level at a lower cost than bottom-up approaches.Comment: 11 pages, 1 figur

CloudHealth: A Model-Driven Approach to Watch the Health of Cloud Services

Cloud systems are complex and large systems where services provided by different operators must coexist and eventually cooperate. In such a complex environment, controlling the health of both the whole environment and the individual services is extremely important to timely and effectively react to misbehaviours, unexpected events, and failures. Although there are solutions to monitor cloud systems at different granularity levels, how to relate the many KPIs that can be collected about the health of the system and how health information can be properly reported to operators are open questions. This paper reports the early results we achieved in the challenge of monitoring the health of cloud systems. In particular we present CloudHealth, a model-based health monitoring approach that can be used by operators to watch specific quality attributes. The CloudHealth Monitoring Model describes how to operationalize high level monitoring goals by dividing them into subgoals, deriving metrics for the subgoals, and using probes to collect the metrics. We use the CloudHealth Monitoring Model to control the probes that must be deployed on the target system, the KPIs that are dynamically collected, and the visualization of the data in dashboards.Comment: 8 pages, 2 figures, 1 tabl

Ensuring Cyber-Security in Smart Railway Surveillance with SHIELD

Modern railways feature increasingly complex embedded computing systems for surveillance, that are moving towards fully wireless smart-sensors. Those systems are aimed at monitoring system status from a physical-security viewpoint, in order to detect intrusions and other environmental anomalies. However, the same systems used for physical-security surveillance are vulnerable to cyber-security threats, since they feature distributed hardware and software architectures often interconnected by ‘open networks’, like wireless channels and the Internet. In this paper, we show how the integrated approach to Security, Privacy and Dependability (SPD) in embedded systems provided by the SHIELD framework (developed within the EU funded pSHIELD and nSHIELD research projects) can be applied to railway surveillance systems in order to measure and improve their SPD level. SHIELD implements a layered architecture (node, network, middleware and overlay) and orchestrates SPD mechanisms based on ontology models, appropriate metrics and composability. The results of prototypical application to a real-world demonstrator show the effectiveness of SHIELD and justify its practical applicability in industrial settings

Department of Computer Science Activity 1998-2004

This report summarizes much of the research and teaching activity of the Department of Computer Science at Dartmouth College between late 1998 and late 2004. The material for this report was collected as part of the final report for NSF Institutional Infrastructure award EIA-9802068, which funded equipment and technical staff during that six-year period. This equipment and staff supported essentially all of the department\u27s research activity during that period

Management and Service-aware Networking Architectures (MANA) for Future Internet Position Paper: System Functions, Capabilities and Requirements

Future Internet (FI) research and development threads have recently been gaining momentum all over the world and as such the international race to create a new generation Internet is in full swing: GENI, Asia Future Internet, Future Internet Forum Korea, European Union Future Internet Assembly (FIA). This is a position paper identifying the research orientation with a time horizon of 10 years, together with the key challenges for the capabilities in the Management and Service-aware Networking Architectures (MANA) part of the Future Internet (FI) allowing for parallel and federated Internet(s)

Knowledge transfer in a tourism destination: the effects of a network structure

Tourism destinations have a necessity to innovate to remain competitive in an increasingly global environment. A pre-requisite for innovation is the understanding of how destinations source, share and use knowledge. This conceptual paper examines the nature of networks and how their analysis can shed light upon the processes of knowledge sharing in destinations as they strive to innovate. The paper conceptualizes destinations as networks of connected organizations, both public and private, each of which can be considered as a destination stakeholder. In network theory they represent the nodes within the system. The paper shows how epidemic diffusion models can act as an analogy for knowledge communication and transfer within a destination network. These models can be combined with other approaches to network analysis to shed light on how destination networks operate, and how they can be optimized with policy intervention to deliver innovative and competitive destinations. The paper closes with a practical tourism example taken from the Italian destination of Elba. Using numerical simulations the case demonstrates how the Elba network can be optimized. Overall this paper demonstrates the considerable utility of network analysis for tourism in delivering destination competitiveness.Comment: 15 pages, 2 figures, 2 tables. Forthcoming in: The Service Industries Journal, vol. 30, n. 8, 2010. Special Issue on: Advances in service network analysis v2: addeded and corrected reference

Dynamic Capabilities and Strategic Management: Explicating the Multi-Level Nature of Dynamic Capabilities - Insights from the Information Technology Security Consulting Industry

The dynamic capabilities perspective has become one of the most vibrant approaches to strategic management. Despite its growing popularity, it has faced criticism because of ambiguity and contradictions in dynamic capabilities literature. There has been increasing calls to address the fragmentation in the literature and provide empirically collaborated insights if it is to fulfil its potential as a distinct approach to strategic management. The microfoundations research agenda remains an emerging theme in the dynamic capabilities literature and since the overarching emphasis of a microfoundational approach is in the explanatory primacy of the micro-level especially in its relation to macro-level entities, it covers a wide array of subjects at several levels. One of the main criticisms of the microfoundations approach is a lack of multi-level analysis and there has been calls for multi-level theory development to connect levels within particular contexts since dynamic capabilities are path dependent and context-specific. This thesis explores the multi-level nature of dynamic capabilities in the Information Technology Security context and empirically investigates the impact of microfoundations of dynamic capabilities on firm capability renewal and reconfiguration. It overcomes the challenge associated with fragmentation in dynamic capabilities by presenting a conceptual model for the multi-level nature of dynamic capabilities. By explicating where dynamic capabilities reside, we can more purposely impact on them to advance our scholarly understanding and proffer practical managerial interventions to directly enhance specific abilities of sensing, seizing and reconfiguring to achieve superior outcomes. The research employed the Gioia qualitative case study research methodology and research methods used were 35 semi-structured interviews and observations. The research findings suggest that firms renew and reconfigure their capabilities to align with the changing industry and industry standards, and client needs. Firms also renew and reconfigure capabilities and capability framework due to internal strategic organisational learning and to align with firm’s specific business strategies. Capability renewal and reconfiguration is vital to achieve technical and evolutionary fitness. In addition, findings inform that dynamic capabilities in the form of ability to sense, seize and reconfigure exhibit at macro, meso and micro levels. Actor’s external engagement with significant institutions enables superior sensing ability. Accumulated experience is exploited to gain credibility with clients to win business, and demystifying firm processes and clarity of language in firm artefacts achieve superior knowledge articulation and codification processes by actors. Structuring of simple routines and capabilities enable ease of internal knowledge transfer but susceptibility to intellectual property theft by outsiders whereas complex routines and capabilities create challenges for knowledge transfer but are harder for competitors to discern and copy. Drawing on the research findings, the thesis presents a conceptual model for the multi-level microfoundations of dynamic capabilities in knowledge-intensive domains with relevance for theory and practice

Optimizing mobile applications by exploiting variability models at runtime

El servicio de reconfiguración dinámica genera y despliega configuraciones de la aplicación optimizadas para el contexto de la ejecución. Para la generación eficiente de estas configuraciones se han definido los algoritmos genéticos DAGAME (mono-objetivo) y MO-DAGAME (multi-objetivo). Ambos algoritmos han sido evaluados, obteniendo buenos resultados con respecto al tiempo de ejecución y a la calidad de las configuraciones generadas. Fecha de lectura de Tesis Doctoral: 18 de diciembre 2018.Los teléfonos móviles inteligentes son una herramienta indispensable en nuestra vida cotidiana. Son dispositivos con los que podemos ejecutar aplicaciones y tareas complejas en cualquier lugar y en cualquier momento. Estas aplicaciones están fuertemente relacionadas con su contexto (e.g., localización, recursos disponibles, etc.) y los requisitos del usuario cambian cuando lo hace el contexto en el que se ejecutan. Por lo tanto, desarrollar aplicaciones que se adaptan al contexto es fundamental para satisfacer dichos requisitos y, para lograrlo, es necesario proporcionar mecanismos de reconfiguración dinámica. Un enfoque ampliamente aceptado para gestionar la variabilidad de las aplicaciones en tiempo de ejecución son las Líneas de Producto Software Dinámicas (DSPLs). Por otro lado, otro paradigma ampliamente aceptado en la comunidad de los sistemas distributidos es el de la Computación Autónoma (CA), cuyo principal objetivo es dotar a los sistemas distribuidos de capacidades de auto-gestión. Esta tesis explora la aplicación de las DSPLs y la CA al desarrollo de aplicaciones para dispositivos móviles que pueden ser reconfiguradas en tiempo de ejecución en función de su contexto. Sus contribuciones cubren tanto el diseño de la DSPL como el desarrollo de mecanismos de reconfiguración dinámica. Con respecto al diseño de la DSPL, se han propuesto dos alternativas diferentes para la especificación de la arquitectura software y la variabilidad. Por un lado, un mecanismo basado en el uso de perfiles UML y herramientas para modelos de características. Por otro lado, un mecanismo basado en el uso del lenguaje CVL para el modelado de la variabilidad. Para la adaptación de las aplicaciones en tiempo de ejecución se ha definido un middleware que incluye servicios de monitorización del contexto y de reconfiguración dinámica