The rapidly developing ad-hoc network technology has a wide range of applications, such as vehicular ad-hoc networks (VANETs), wireless sensor networks (WSNs), and emergency and military communications. Due to the characteristics such as openness and dynamic topology, ad-hoc networks suffer from various attacks in the data plane. Even worse, some attacks can subvert or bypass the frequently used identity-based security mechanisms. To secure the data plane of ad-hoc networks, we propose a novel trust management system.