Waleed Wagealla

Using trust for secure collaboration in uncertain environments

The SECURE project investigates the design of security mechanisms for pervasive computing based on trust. It addresses how entities in unfamiliar pervasive computing environments can overcome initial suspicion to provide secure collaboration.

Trusting collaboration in global computing systems

A significant characteristic of global computing is the need for secure interactions between highly mobile entities and the services in their environment. Moreover, these decentralised systems are also characterised by partial views over the state of the global environment, implying that we cannot guarantee verification of the properties of the mobile entity entering an unfamiliar domain. Secure in this context encompasses both the need for cryptographic security and the need for trust, on the part of both parties, that the interaction will function as expected. In this paper, we explore an architecture for interaction/ collaboration in global computing systems. This architecture reflects the aspects of the trust lifecycle in three stages: trust formation, trust evolution and trust exploitation, forming a basis for risk assessment and interaction decisions.

Engineering Trust Based Collaborations in a Global Computing Environment

Trust management seems a promising approach for dealing with security concerns in collaborative applications in a global computing environment. However, the characteristics of this environment require a move from reliable identification to mechanisms for the recognition of entities. Furthermore, they require explicit reasoning about the risks of interactions, and a notion of uncertainty in the underlying trust model. From our experience of engineering collaborative applications in such an environment, we found that the relationship between trust and risk is a fundamental issue. In this paper, as an initial step towards an engineering approach for the development of trust based collaborative applications, we focus on the relationship between trust and risk, and explore alternative views of this relationship. We also exemplify how particular views can be exploited in two particular application scenarios. This paper builds upon our previous work in developing a general model for trust based collaborations.

Some Research Challenges in Pervasive Computing

The topics of privacy, security and trust have become high priority topics in the research agenda of pervasive computing. Recent publications have suggested that there is or at least needs to be a relationship of research in these areas with activities in context awareness. The approach of the workshop, on which this proceedings reports, was to investigate the possible interfaces between these different research strands in pervasive computing and to define how their concepts may interoperate. This first article is therefore the introduction and overview of the workshop, providing some background on pervasive computing and its challenges.

Trust dynamics for collaborative global computing

Recent advances in networking technology have increased the potential for dynamic enterprise collaborations between an open set of entities on a global scale. The security of these collaborations is a major concern, and requires novel approaches suited to this new environment to be developed. Trust management appears to be a promising approach. Due to the dynamic nature of these collaborations, dynamism in the formation, evolution and exploitation of trust is essential. In this paper, we explore the properties of trust dynamics in this context. Trust is formed and evolves according to personal experience and recommendations. The properties of trust dynamics are expressed through a formal model of trust. Specific examples, based on an e-purse application scenario are used to demonstrate these properties.

Towards an evaluation methodology for computational trust systems

Trust-based security frameworks are increasingly popular, yet few evaluations have been conducted. As a result, no guidelines or evaluation methodology have emerged that define the measure of security of such models. This paper discusses the issues involved in evaluating these models, using the SECURE trust-based framework as a case study.

Considering trust in ambient societies

The Challenge: The Uses and Abuses of Trust in Ambient Technology and Mobile Users By having multiple mobile, ‘smart,’ ubiquitous devices, we have introduced the social world to the technological world. The results are going to be chaotically interesting. The challenge for the HCI world is to unify the various attempts at bringing formal models of trust in information, technology and each other so that the technology can operate in a trusted and trustworthy manner in a human environment. The challenge, then, is to design interfaces and interaction that allows people to get the most out of the technology without falling prey to its inadequacies.

Trust lifecycle management in a global computing environment

In a global computing environment in order for entities to collaborate, they should be able to make autonomous access control decisions with partial information about their potential collaborators. The SECURE project addresses this requirement by using trust as the mechanism for managing risks and uncertainty. This paper describes how trust lifecycle management, a procedure of collecting and processing evidence, is used by the SECURE collaboration model. Particular emphasis is placed on the processing of the evidence and the notion of attraction. Attraction considers the effects of evidence about the behaviour of a particular principal on its current trust value both in terms of trustworthiness and certainty and is one of the distinctive characteristics of the SECURE collaboration making it more appropriate for a global computing setting.