The i* Strategic Dependency model has been successfully employed to analyze trust relationships of networks of agents during the early stages of multiagent systems development. However, the model only supports limited trust reasoning due to its limitation to deal with the vulnerability of the depender regarding the failure of the dependency. In this paper, we introduce the concept of willingness, which provides a solution to the above problem and therefore allows a more complete analysis and reasoning of trust relationships in networks of agents.

This paper introduces generic delegation patterns modeled with the strategic actors of the i* framework. We argue that this modeling approach together with reasoning mechanisms offers a potentially more substantive approach to understand the nature of delegation relationships in a variety of social and technical contexts. Furthermore, we hope that understanding the underlying assumptions and constructs through the use of the delegation modeling framework will not only inform analysts of a better design for delegation policies, but also assist in the understanding of intricate situations in which different delegation models appear.

This paper introduces service delegation modeling framework based on the strategic actors concept of the i* framework. We argue that this modeling approach together with reasoning mechanisms offers a potentially more substantive approach to understand the nature of delegation behavior in the service setting. Furthermore, we hope that understanding the underlying assumptions and constructs through the use of the delegation modeling framework will not only inform analysts of a better design for delegation mechanisms, but also assist in the understanding of intricate situations in which different delegation scenarios appear. We present a content service delegation scenario as a proof-of-concept example to illustrate the proposed approach

Multi-agent systems (MAS) are now being considered a promising architectural approach for designing collaborative information systems. In such a perspective, the concept of delegation has often been considered as a key concept for modeling cooperative behavior in MAS. However, despite considerable work on delegation mechanisms in MAS, few research efforts have aimed at truly defining a delegation model for designing MAS. This paper deals with this issue in defining the foundations for a delegation model aimed to help developers during the phase of designing collaborative MAS.

Securing an information system (IS) involves continual de- tection and response to security obstacles at all stages of the system's lifecycle. During early requirements engineering, one way to facilitate these tasks is to use secure actor and goal models that represent desired IS behaviour, including responses to security obstacles. We propose the Security Obstacle Detection and Response (SODR) method for detecting and responding to security obstacles during the construction of secure actor and goal models in early RE. SODR relies on a justication pro- cess, in which arguments about potential security obstacles related to IS assets are made explicit, submitted to justication, leading either to the identication of justied responses to the given security obstacles or the rejection of these obstacles. SODR thereby ensures that the argu- ments behind the identied security obstacles and chosen responses are explicit, so that they can be constructed, openly questioned, and revised in a structured and rigorous manner. The proposed method is supported by the SODR-Tool.