Abstract
The simulation framework VSimRTI allows for the integration of multiple heterogeneous simulators to enable V2X application simulations. In order toincrease performance and scalability of complex V2X simulations, a new time management service has been implemented that enables optimistic synchronization in federated simulations. This paper presents the underlying mechanisms as well as the resulting system architecture. To evaluate the improvements that can be achieved, different experiments with highly configurable virtual federates as well as real simulators have been realized. The experiments show the conditions for an improvement by optimistic synchronization mechanisms and demonstrate the performance increase that can be achieved.