Abstract
Multi-issue negotiation protocols represent a promising field sincemost negotiation problems in the real world involve multiple issues. Our work focuses on negotiation with multiple interdependent issues in which agent utility functions are nonlinear. Firstly, we define utility function based on cone-constraints which are nonlinear. The utility function based on cone-constraint is more realistic than existing utility models and configures the risk attitudes to the cone-constraint. However, if the utility function has cone-constraint features, the utility space becomes extremely nonlinear, making it very difficult to find the optimal agreement point. Existing works have not yet concerned with agents' private information that should be concealed from others in negotiations. In this paper, we propose Distributed Mediator Protocol and Take it or Leave it Protocol for negotiation that can reach agreements and completely conceal agents’ private information. Moreover, we propose Hybrid Secure Protocol that combines Distributed Mediator Protocol with Take it or Leave it Protocol. The Hybrid Secure Protocol can also reach agreements while completely concealing agents’ private information. Furthermore, the Hybrid Secure Protocol achieves high optimality and uses less communication cost. We demonstrate the performance of Hybrid Secure Protocol in cone-constraints and cube-constraints situations.