I Tube, YouTube, P2PTube: Assessing ISP benefits of peer-assisted caching of YouTube content

The last few years have seen an explosion of video on demand traffic carried over the Internet infrastructure. While P2P applications have been proposed to carry VoD and TV content, they have so far encountered limited adoption except in Asian countries. Part of why this happens is explained with the fact that (i) the current asymmetric network infrastructure does not offer enough system capacity needed to let a fully P2P-VoD/TV to be self-sustainable, (ii) that the actual capacity at nominal peers is often smaller than the available one due to inefficiency in NAT punching[1], and (iii) the very same nonelastic nature of the service, that makes the system inherently less robust w.r.t elastic file-sharing to dynamic changes in the istantaneously available bandwidth. The other part of the story can be summarized with the success of CDN-managed services such as Netflix, Hulu and especially YouTube - according to [2], about 3 billion YouTube videos are viewed and 100´s of thousand videos are uploaded every day, with independent research confirming YouTube to represent 20-30% of ISPs incoming traffic[3]^.