It has been in the news recently that the carbon footprint of Netflix and other streaming services is significant.1.6 Kg of carbon dioxide per ½ hour viewing is on the high side of the estimates, 451,000 megawatt hours for the whole world is on low side. An alternative technology for accessing such media is bittorrent. Without considering the legal aspects, how would the carbon footprint of getting your media from bittorrent compare with getting it from Netflix?
I'm not sure what P2P protocol was used and if results for BitTorrent would be the same, but in this study they calculated
a decrease of 24-48% in the system-wide carbon footprint of online video streaming
when using P2P compared to Content Delivery Networks. The paper describes that this is mainly because of
selecting close by peers to share content from leads to shorter paths compared to traditional CDNs.
There are however a few caveats:
- There is little incentive for ISPs to participate as their traffic is only going up
- The difference in download and upload bandwidth and different peers having different download speeds can limit the gains.
- I read that a lot of Netflix traffic goes to mobile devices which are less suitable to use P2P networking
- The paper compared a traditional CDN to a hybrid one where data is downloaded from peers where possible. I'm not sure what technology Netflix is using. There were reports in 2014 that they were hiring P2P engineers, but as far as I can gather Netflix is not using such technology yet.