ozmanjusri writes "Several American ISPs have been throttling their YouTube caches to the extent that the content is almost unwatchable. Many ISPs had caching agreements are in place with Google to improve performance but have chosen to reduce load (and therefore quality) instead.
To fix the problem on Linux, use iptables to reject the throttled cache and go direct to Google servers:
sudo iptables -A INPUT -s 188.8.131.52/24 -j REJECT
sudo iptables -A INPUT -s 184.108.40.206/16 -j REJECT
While it's possible the throttling happens because caches are bottlenecked or overloaded somewhere in the ISPs' network, complaints to forums have elicited 'We have no problems' responses."
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