Real-time video frame differentiation in multihomed VANETs

Providing high quality video transmission in VANETs is very challenging due to the highly dynamic, unpredictable topology, and low bandwidth characteristics. In this article, we design a system able to optimally transmit RTP video streams in an IP-based multihomed VANET. By splitting the video through its different frame types in the array of multihomed paths from the center node of the network to the clients, the system can then send critical frames, depending on the used coding standard, through a more reliable path, in order to improve the video performance even if the quality is degraded due to bad signal reception. Two different content-based multihomed video distribution schemes have been proposed: linear selection, where the system is able to select more reliable paths for higher prioritized segments; and adaptive selection, where the paths are sensed to assess their congestion level in a real-time approach. Through real deployment of these approaches in a real vehicular scenario, with mobility, handovers and multihoming, the proposed approaches achieved a strong decrease in the loss percentage, with a maximum of approximately 60.4%, greatly improving the video quality while on the move.