Topology aware feedback transmission for real-time control protocol

Abstract

Real-time Transport Protocol (RTP) is a protocol for delivering time sensitive data such as audio and video over the Internet. RTP is usually used in conjunction with Real-time Control Protocol (RTCP), which provides statistics about flow of data using RTP. Certain problems related to RTCP scalability have arisen, mostly due to growth in the IPTV market and higher demands on bigger broadcasting sessions. Several solutions based on tree structures such as S-RTCP, MS-RTCP, TTP and others have been introduced. This paper proposes a method for constructing an optimal and well organized hierarchical tree structure with respect to standard RTCP. The proposed method can be integrated with most of the current solutions, including S-RTCP, MS-RTCP and TTP. Experience gained by us deploying our method on a global research network called PlanetLab is also discussed at the end of this paper.