
Spotify – Large Scale, Low Latency, P2P Music-on-Demand Streaming [pdf] - wspruijt
http://www.csc.kth.se/~gkreitz/spotify-p2p10/spotify-p2p10.pdf
======
xtacy
Are ISPs okay with organizations using P2P to offload their bandwidth
requirements to clients?

[http://arstechnica.com/web/news/2009/02/cnn-p2p-video-
stream...](http://arstechnica.com/web/news/2009/02/cnn-p2p-video-streaming-
tech-raises-questions.ars)

~~~
sp332
I'm not sure I understand - the data has to come from somewhere, and go
somewhere. If both endpoints are on the same last-mile ISP, the ISP wins
because there's less traffic to and from peers, so their peering costs are
lower. Other than that, why would it matter if the data came from a central
server or from some other PC?

~~~
xtacy
I agree that if the end points are inside the ISP, it's good.

But peering is different from transit; peering is a delicate relationship
where ISPs route traffic to each other for "free", as long as the demands are
not too asymmetric. If this software results in a lot of traffic generated
from a peering ISP, then it could be causes of worry for the receiving ISP.

~~~
sp332
But the "receiving" ISP is only receiving the data because its users asked for
it. It doesn't make a difference if the data comes from a Spotify server or
from a PC. It's still the same amount of data being transferred.

~~~
wmf
Receiving data over a transit connection may be more expensive than from a
CDN. In DOCSIS networks, P2P also tends to introduce last-mile upstream
congestion which is expensive to fix.

~~~
themal
The last mile problem is presumably exasperated by P2P users being mostly
consumers, rather than businesses, and therefore paying next to nothing for
the connections.

------
sherbondy
The very fact that the Spotify team was willing to publish this paper
demonstrates how confident they are in their offering. Spotify is (albeit at a
high level of abstraction) telling competitors exactly how its service works!
They’re begging Amazon and Google and Apple and the likes to copy their model.
Those are some cojones.

------
jorangreef
Great paper.

