Dynamic inter-organizational cooperation setup in Circle-of-Trust environments

The need for collaborative service provisioning across different providers' domains is being addressed by Circles of Trust (CoT), whose members adhere to the same policies and expose the same interfaces for collaboration. Today's CoT specifications require a high initial effort on behalf of enrolling members, thus obviating quick or even ad hoc setup of business cooperation with entities outside a CoT. We explore a procedure that complements the static aspects of the CoT by a dynamic assessment of trust levels between organizations. Its benefit lies in the shortened setup time for a business interaction, which can be achieved by automating the assessment process. The appraisement of a potential partner outside a CoT leverages existing CoT members' experience. We propose algorithms suitable for calculating trust values and discuss alternative solutions to be used where reputation-based assessment within the CoT is impossible.