| At least three factors regarding rationing of bandwidth: Data rate, data volume and caching. "Bandwidth" is already rationed but is usually high enough you don't notice most of the time or its still good enough most of the time. If you do continuous transfers you immediately see the data rate limits already in place. But these data rate limits are usually already throttled and therefore different to some monthly download data cap. Those data caps are often marketing/sales driven rather than the actual data rate. And often the real technical data volume limits are for data entering/leaving the ISP. That's the real cost that is being covered by bandwidth caps. They estimate the costs at their borders and cover that first. Which brings us to the caching involved. The more caching the easier it is to lower costs or limits. Peering means that some ISPs are closer to each other than they otherwise would be. And Netflix and others using CDNs etc place servers at strategic locations to bring themselves closer. That 2GB movie stream is likely traversing a lot less equipment than you'd expect. In some cases, less than a video conference or game. If caching fails and something got broken along the way, or... they don't have a close enough CDN site, or caching simply isn’t possible, that is when you have congestion[1] since your traffic now joins whatever else is at the ISP entry/exit points. They can still lower your data rate without touching some monthly data cap. [1] I'm not discounting congestion within an ISPs network but as they have all the dials and can do whatever they like to sort that out its a separate issue. Redundant paths are a thing. Also, if they isolate congestion to a particular user or usage, eg bittorrent, they already have throttling for that. |