Rate Adaptive Real-Time Video Transmission Scheme over TCP Using Multi-Buffer Scheduling

We explore the process of transmitting real-time Internet video frames over TCP (Transmission Control Protocol) and discover that the delay of waiting in TCP sender-buffer is the critical factor that causes large end-to-end delay. We propose a multi-buffer scheduling model for decreasing the end-to-end delay by scheduling video frames among application-layer sender-buffer, TCP sender-buffer, TCP receiver-buffer and receiver playout-buffer. Based on the proposed model, we present a new rate adaptive scheme to dynamically deliver variant bit rate video frames according to available network bandwidth by adjusting frame rate as well as assuring video frames to be played at normal time. Our scheme does not require any modifications to the network infrastructure or TCP protocol stack and only needs an application-layer buffer of sender. The performance of the proposed solution is evaluated through extensive simulations using the NS-2 simulator.