Feedback transmission in large-scale IPTV sessions

In this paper, we introduce the Tree Transmission Protocol (TTP), which we use for the organization of a tree structure consisting of IPTV nodes for hierarchical feedback aggregation in large-scale IPTV (Internet Protocol Television) systems. The feedback transmission is based on the hierarchical feedback aggregation algorithm, which gives a lower feedback reporting interval compared with the standard feedback transmission in the RTP/RTCP protocol stack. We use the TTP protocol to establish a tree structure by grouping IPTV nodes into groups using a defined set of parameters. One of the parameters we use is the logical position of the IPTV nodes. The motivation for utilizing this parameter in the TTP protocol is to optimize communication in the created overlay network for feedback transmission. We use the Vivaldi algorithm for the localization of the IPTV nodes. In this paper, we also describe the implementation of the TTP protocol on the PlanetLab experimental network as well as the application, we used for the visualization of the established tree.