An adaptive algorithm for real-time data transmission in multi-hop overlay networks

Aiming at improving the performance of real-time data transmission in multi-hop overlay networks, an adaptive flow control transmission algorithm is proposed. The approach considers the reality of low bandwidth and the requirement of high throughput in real-time media streaming so that it takes the forwarding capability of relay peers as the main evaluation metric. Probe data packets are introduced to real-time data transmission to help derive necessary feedback information. Receivers periodically calculate their available buffer size and send feedbacks to senders who use them to adjust the transmission rates. The mechanism for the dynamic adjustment of bandwidth requirements in media streaming is based on an adaptive rate threshold which adjusts the transmission rate according to the available bandwidth. Redundant flow resources are distributed to multiple relay links. Theoretical analysis and simulations indicate that the cooperative transmission algorithm is able to decrease the transmission failure rate and reduce the whole transmission delay of real-time applications in multi-hop overlay networks.