In this paper we introduce unconditionally secure distributed delegation systems that allow groups of participants to collectively authorize a delegate to sign a message (construct an authentic message) on their behalf. We propose a model and investigate its properties when delegation is valid for one transmission. The model is extended to multiple delegation and constructions with more economi...

Automated Web Service Composition has gained a significant momentum in facilitating fast and efficient formation of business-to-business collaborations where an important objective is the utilization of existing services to respond to new business requirements in a timely manner. In this context, the service delegation problem can be formulated as follows: When a user poses a sequence of reques...

At present, many countries allow citizens or entities to interact with the government outside the telematic environment through a legal representative who is granted powers of representation. However, if the interaction takes place through the Internet, only primitive mechanisms of representation are available, and these are mainly based on nondynamic offline processes that do not enable quick ...

The Canadian Department of National Defence (DND) is shifting its methods for the delegation and exercise of authority from paper-based to electronic-based means. DND has deployed a commercial PKI but there is no general technical solution presently employed by DND for access control or electronic authorization of workflow in distributed processing environments. The aim of this research is to s...

Delegation is a widely used and widely studied mechanism in access control systems. Delegation enables an authorized entity to nominate another entity as its authorized proxy for the purposes of access control. Existing delegation mechanisms tend to rely on manual processes initiated by end-users. We believe that systems in which the set of available, authorized entities fluctuates considerably...

This paper examines the commitment e ect of delegated bargaining when renegotiation of the delegation contract cannot be ruled out. We consider a seller who can either bargain face-to-face with a prospective buyer or hire an intermediary to bargain on her behalf. The intermediary is able to interrupt his negotiation with the buyer to renegotiate the delegation contract. In this model, the time ...

Access control is important for protecting information integrity in workflow management system (WfMS). Compared to conventional access control technology such as discretionary, mandatory, and role-based access control models, task-role-based access control (TRBAC) model, an access control model based on both tasks and roles, meets more requirements for modern enterprise environments. However, f...

We present HM-ABE, a hierarchical multi-authority attributebased encryption scheme with policy delegation, that generalizes current work significantly. Current methods require encryptors to build ciphertext access policies themselves, using attributes published by authority domains. This causes problems, both since authorities may not publish sensitive attributes, and since users may not unders...

This paper explains the evolution of the concept of delegation since its first references in the context of distributed authorization to the actual use as a fundamental part of a privilege management architecture. The work reviews some of the earliest contributions that pointed out the relevance of delegation when dealing with distributed authorization, in particular we comment on PolicyMaker a...

OBJECTIVE To develop a method enabling human-like, flexible supervisory control via delegation to automation. BACKGROUND Real-time supervisory relationships with automation are rarely as flexible as human task delegation to other humans. Flexibility in human-adaptable automation can provide important benefits, including improved situation awareness, more accurate automation usage, more balanc...