Network Security Supported by Arguments

Argumentation has been proved as a simple yet powerful approach to manage conflicts in reasoning with the purpose to find subsets of ?surviving? arguments. Our intent is to exploit such form of resolution to support the? administration of security in complex systems, e.g., in case threat countermeasures are in conflict with non-functional requirements. The proposed formalisation is able to find the required security controls and explicitly provide arguments supporting this selection. Therefore, an explanation automatically comes as part of the suggested solution, facilitating human comprehension

Cost-Effective Enforcement of Access and Usage Control Policies under Uncertainties

In Usage CONtrol (UCON) access decisions relyon mutable attributes. A reference monitor should re-evaluatesecurity policies each time attributes change their values. Identifyingall attribute changes in a timely manner is a challengingissue, especially if the attribute provider and the referencemonitor reside in different security domains. Some attributechanges might be missed, corrupted, and delayed. As a result,the reference monitor may erroneously grant access to malicioususers and forbid it for eligible ones.This paper proposes a set of policy enforcement modelswhich help to mitigate the uncertainties associated with mutableattributes. In our model the reference monitor, as usual, evaluateslogical predicates over attributes and, additionally, makes someestimates on how much observed attribute values differ from thereal state of the world. The final access decision takes into accountboth factors. We assign costs for granting and revoking access tolegitimate and malicious users and compare the proposed policyenforcement models in terms of cost-efficiency

Formal Analysis of Security Metrics and Risk

Abstract. Security metrics are usually defined informally and, therefore, the rigourous analysis of these metrics is a hard task. This analysis is required to identify the existing relations between the security metrics, which try to quantify the same quality: security. Risk, computed as Annualised Loss Expectancy, is often used in order to give the overall assessment of security as a whole. Risk and security metrics are usually defined separately and the relation between these indicators have not been considered thoroughly. In this work we fill this gap by providing a formal definition of risk and formal analysis of relations between security metrics and risk

La interfaz, espacio de interacción en la formación de la experiencia cognitiva de usuarios del arte digital

La investigación presenta una construcción del estudio de las interfaces, en tanto espacios de interacción donde los usuarios forman una experiencia cognitiva determinada a través de diversos procesos en relación al escenario híbrido que recrea el arte digital. Se sustenta en una conceptualización a partir del marco teórico de Carlos Scolari centrado en el modelo semio-cognitivo de las interacciones donde se estudia a detalle a la interfaz, al espacio de interacción, a los modelos mentales que construyen los diseñadores respecto de las interfaces y especialmente a los modelos mentales de los usuarios. Asimismo se presenta una conceptualización del arte digital y por tanto del arte contemporáneo actual. El estudio es de tipo cualitativo, se emplearon técnicas de observación y de entrevista semiestructurada aplicadas a diecinueve usuarios y a tres diseñadores en un festival de arte digital efectuado en la Ciudad de México en febrero de 2012

Usage Control, Risk and Trust

Abstract. In this paper we describe our general framework for usage control (UCON) enforcement on GRID systems. It allows both GRID services level enforcement of UCON as well as fine-grained one at the level of local GRID node resources. In addition, next to the classical checks for usage control: checks of conditions, authorizations, and obligations, the framework also includes trust and risk management functionalities. Indeed, we show how trust and risk issues naturally arise when considering usage control in GRID systems and services and how our architecture is flexible enough to accommodate both notions in a pretty uniform way

Comprehensive Approach to Increase Cyber Security and Resilience

In this paper the initial results of the European project CAMINO in terms of the realistic roadmap to counter cyber crime and cyber terrorism are presented. The roadmap is built in accordance to so called CAMINO THOR approach, where cyber security is perceived comprehensively in 4 dimensions: Technical, Human, Organizational, and Regulatory

MEDINA Risk Assessment - User Manual

Risk assessment functionality is implemented in MEDINA with a Self-Assessment Tool for Risk Analysis (SATRA), which realises a Risk Assessment and Optimisation Framework (RAOF) component

From Early Requirements to Business Processes with Service Level Agreements

When designing a service-based business process employing loosely-coupled services, one is not only interested in guaranteeing a certain flow of work, but also in how the work will be performed. This involves the consideration of non-functional properties which go from execution time, costs, up to security and trust. Ideally, a designer would like to have guarantees over the behavior of the services involved in the process. These guarantees are the object of Service Level Agreements. We propose a methodology to design service-based business processes together with service level agreements that guarantee a certain quality of execution, with particular emphasis on the security aspects. Starting from an early requirements analysis modeled in the SI* formalism, we provide a set of user-guided transformations and reasoning tools which final output is a set of processes, in the form of Secure BPELs, together with a set of service level agreements to be signed by participating services. To show the potential impact on security guarantees, we illustrate the functioning of the methodology on a e-business banking example inspired by an actual industrial case

From Early Requirements to Business Processes with Service Level Agreements ⋆

Abstract. When designing a service-based business process employing loosely-coupled services, one is not only interested in guaranteeing a certain flow of work, but also in how the work will be performed. This involves the consideration of non-functional properties which go from execution time, costs, up to security and trust. Ideally, a designer would like to have guarantees over the behavior of the services involved in the process. These guarantees are the object of Service Level Agreements. We propose a methodology to design service-based business processes together with service level agreements that guarantee a certain quality of execution, with particular emphasis on the security aspects. Starting from an early requirements analysis modeled in the SI * formalism, we provide a set of user-guided transformations and reasoning tools which final output is a set of processes, in the form of Secure BPELs, together with a set of service level agreements to be signed by participating services. To show the potential impact on security guarantees, we illustrate the functioning of the methodology on a e-business banking example inspired by an actual industrial case.

Analysis of Social Engineering Threats with Attack Graphs

Abstract. Social engineering is the acquisition of information about computer systems by methods that deeply include non-technical means. While technical security of most critical systems is high, the systems remain vulnerable to attacks from social engineers. Social engineering is a technique that: (i) does not require any (advanced) technical tools, (ii) can be used by anyone, (iii) is cheap. While some research exists for classifying and analysing social engineering attacks, the integration of social engineering attackers with other attackers such as software or network ones is missing so far. In this paper, we propose to consider social engineering exploits together with technical vulnerabilities. We introduce a method for the integration of social engineering exploits into attack graphs and propose a simple quantitative analysis of the graphs that helps to develop a comprehensive defensive strategy