A number of commercial peer-to-peer systems for live streaming, such as PPLive, Joost, LiveStation, SOPCast, TVants, etc. have been introduced in recent years. The behavior of these popular systems has been extensively studied in several measurement papers. Due to the proprietary nature of these commercial systems, however, these studies have to rely on a "black-box" approach, where packet traces are collected from a single or a limited number of measurement points, to infer various properties of traffic on the control and data planes. Although such studies are useful to compare different systems from end-user's perspective, it is difficult to intuitively understand the observed properties without fully reverse-engineering the underlying systems. Our paper presents a large-scale measurement study of Zattoo, one of the largest production live streaming providers in Europe, using data collected by the provider. To highlight, we found that even when the Zattoo system was heavily loaded with as high as 20,000 concurrent users on a single overlay, the median channel join delay remained less than 2 to 5 seconds, and that, for a majority of users, the streamed signal lags over-the-air broadcast signal by no more than 3 seconds. To motivate the measurement study, we also present a description of the Zattoo network architecture.
['Hyunseok Chang', 'Sugih Jamin', 'Wenjie Wang']
Live streaming performance of the Zattoo network