BitTorrent-like P2P approaches for VoD: A comparative study

Abstract

The enormous popularity of Video on Demand (VoD) has attracted substantial research attention into the effective use of peer-to-peer (P2P) architectures to provide solutions at large-scale. In particular, the high efficiency of BitTorrent has inspired many P2P protocols for VoD. However, these protocols use different approaches to adapt the design of Bittorrent to VoD, and in most cases their performance has been evaluated separately and in limited scenarios. As a consequence, the research community still lacks a clear understanding of how these protocols compare against each other and how well each of them would work in real world conditions, where, for instance, peers have heterogeneous bandwidths, may freeride or may be located behind NAT/firewall.In this paper, we propose a simulation based methodology which aims at putting forward a common base for comparing the performance of these different protocols under a wide range of conditions. We show that, despite their considerable differences, (i) existing BitTorrent-like VoD approaches all share some characteristics, such as that their bandwidth reciprocity based methods to incentivize cooperation do not always yield an optimal overall performance. Furthermore, we demonstrate that (ii) in these protocols there is a trade-off between QoS and resilience to freeriding and malicious attacks. We also discover that, (iii) when peers doing streaming coexist with peers doing traditional file transfer, the latter actually benefit from this coexistence, at the expenses of the former. Finally, we show that (iv) early departures of peers from the system do not significantly affect the QoS de- livered, while jumping to a different position in the file has a bigger negative impact. Overall, our findings provide important implications for both VoD service providers and future system designers. On the one hand, our results can guide VoD service providers in selecting the most appropriate protocol for a given environment. On the other hand, exposing the flaws of current approaches will help researchers in improving them and/or designing better ones.

A new scheduling mechanism of BitTorrent streaming system based on improved PSO algorithm

“…So we adapt its design to satisfy the fundamental quality-of-service requirements for streaming, while still maintaining the high efficiency of the original BT protocol. Based on [13], we design an adaptive double window mechanism for piece selection, considering the urgency and scarcity of pieces. There are two windows in the video file, emergency window and normal window.…”

Hic sunt NATs: Uncovering address translation with a smart traceroute

“…D'Acunto et al [9] analyzed P2P applications and found that 88% of the participants in the studied P2P network were behind NATs. Sherry et al [3] obtained configurations from 57 enterprise networks and revealed that they can contain as many middleboxes as routers.…”

Improving BitTorrent's Peer Selection for Multimedia Content On-Demand Delivery

“…Plenty of practical P2P approaches, like the BitTorrent protocol [6], have been successful in the past years. In fact, the great efficiency achieved by BitTorrent for the distribution of large amounts of data inspired its adoption for on-demand video streaming [7][8][9].…”

“…Plenty of practical P2P approaches, like the BitTorrent protocol [6], have been successful in the past years. In fact, the great efficiency achieved by BitTorrent for the distribution of large amounts of data inspired its adoption for on-demand video streaming [7][8][9].Peer-Selection Policy is the term assigned to one of the core concepts of BitTorrent. By stimulating direct reciprocity and cooperation, its design specifies who makes use of the uplink capacity from all the peers inside the swarm (i.e., a group of peers downloading a same content).…”

“…As mentioned by Rocha & Rodrigues [21], high interactive users tend to stay less time inside the swarm and consequently are likely to requests less data than peers streaming in a sequential fashion. Also, the segments of data requested are mostly dispersed over the media file, provoking a higher number of interruptions and therefore spending more time on slots for data download.Moreover, if the reader is interested, the studies of D'Acunto et al [9] and Ma et al [23] debate and examine differences achieved in the overall system performance when distinct pieceselection and peer-selection strategies are composed and tested in conjunction [15]. It is important to have this in mind in Section 5, where the new peer selection proposed herein (described in Section 4) is simulated together with a different piece-selection algorithm instead of the original one from BitTorrent.…”