In ITS (Intelligent Transport Systems), many IVC protocols have been developed for running various ITS applications. Although there are various ITS applications in ITS, the most of existing methods focus on communications of specific ITS applications. In order to introduce unified on-board communication unit, it is desirable to run various ITS applications on top of one IVC protocol. In this paper, we propose Condition-based Data Dissemination method (CDD), combining Adaptive Beacon Transmission and Autonomous Packet Forwarding. We evaluate our proposal using simulations, and show the effectiveness of the proposal.