Digital Fountains + P2P for Future IPTV Platforms: A Test-Bed Evaluation

The opportunities laid by the joint use of Peer-to-Peer (P2P) streaming systems and advanced Digital Fountain (DF) codes in the context of Internet Protocol TeleVision (IPTV) platforms have set high expectations for their combined use. P2P streaming strategies, on one hand, have proven to be able to increase the bandwidth efficiency and the consequent scalability of IPTV platforms. DFs, on the other, have found a potential role in improving the bandwidth efficiency and the robustness to high peer churn rates of P2P streaming systems. However, given the complexity of both of such systems and the unexpected possible outputs that may result from their interaction, an effective assessment of their performances requires the design and setup of real world test-beds. In this article we describe the results deriving from a set of experiments performed on a P2P streaming test-bed that integrates DFs. The most prominent result of this experimentation campaign is that DFs do not provide notable improvements to a BitTorrent-based network of limited size, while as the network scales beyond a given size, it is possible to observe important advantages. This work, and, in particular, assessing when the use of DFs can be beneficial, can influence the devise of future IPTV service architecture which could be based on such technologies. We believe this represents a relevant contribution to understanding important aspects of the joint utilization of peer-to-peer multimedia streaming strategies and advanced digital fountain techniques.