Negotiation for authorisation in virtual organisation

In virtual organisations, the authorisation and expression of policies in terms of direct trust relationships between providers and consumers have the problems of scalability, flexibility, expressibility, and lack of policy hierarchy because of interdependent institutions and policies [Pearlman et al. 2003]. This paper proposes a bilateral negotiation protocol and an English auction to negotiate a list of credentials to be exchanged after a service level agreement has been drafted, and that would provide sufficient trustworthiness for the parties in the negotiation. We implement and evaluate our algorithms as grid services in a virtual organisation (VO) to show the effect of negotiation on the trustworthiness achieved within a VO