Push-to-talk service for intelligent transportation systems

Push to talk (PTT) is a walkie-talkie like service. In this service, several predefined group members participate in one PTT session. At any time, only one group member is allowed to speak. Therefore, a mechanism is required to determine the member that is permitted to speak. In Open Mobile Alliance (OMA), a central arbitrator coordinates the permission to speak among the group members. In the Intelligent Transportation System (ITS) environment, the centralized OMA approach is not appropriate. This paper proposes a distributed PTT mechanism for the ITS environment, which does not require any central arbitrator. The group member permitted to speak is automatically determined through distributed learning interaction. We also explore the properties and model the performance of the proposed PTT mechanism.