Quality assessment of the packet transport of peer-to-peer video traffic in high-speed networks

Dealing with the quality of the packet transport of multimedia services in overlay networks, we present the relation between the packet missing probability PmPm of transmitted packets of a variable bitrate video stream and distributions of the length of the overlay path, the upload capacity of nodes and the playback delay at a destination node. As active streams share the capacity of a transport channel, we select an equivalent bandwidth based on a bufferless fluid-flow model. A smallest equivalent capacity u∗u∗ which provides the best trade-off between the mean delay between successfully delivered packets and the mean lossless time that is determined by the duration of consecutive successful packet transmissions is proposed as an optimal upload capacity. u∗u∗ is less than the peak rate. The playback delay bb is selected as a quantile of a packet delay distribution. The normalized distribution of the length of the overlay path is derived to be geometric. The estimation of u∗u∗ and bb requires inter-arrival times between packets, packet lengths of a peer-to-peer video flow and end-to-end packet delays. For SopCast IPTV data it is concluded that the signaling traffic does not impact on u∗u∗ and increasing bb leads to the decrease of PmPm.

Figure optionsDownload as PowerPoint slideHighlights
► We study QoS-issues of the packet transport in peer-to-peer overlay networks.
► We consider a bufferless fluid-flow queue as basic model of a bottleneck link.
► The overlay path length of a packet transport is derived to be geometric distributed.
► The missing probability of the packets is derived as main quality index.
► We estimate upload capacities of peers and a playback delay at destination node.