SORT: A System for Adaptive Transmission of Video Over Delay Tolerant Networks

In challenging environments, opportunistic networks can provide limited communication features in a delay tolerant manner. It is extremely difficult to transmit large data like videos in such environments, as delay may be hours and part of the information may be lost. This article proposes a novel system that uses partial information from prior communication to estimate the network congestion and delay. The video is compressed and packetized using scalable video coding (SVC). Extensions to Spray-and-Wait routing protocols are analyzed to ensure better delivery video quality and lower wastage. Through simulation, including real-world traces, performance of the proposed solutions under multiple scenarios is evaluated. Experimental results show that adaptive control reduces overall delay and minimizes wastage while improving the quality of video at the receiver. Adaptive SVC transmissions demonstrate almost three times increase in decoded content, as compared to non-SVC transmission.