Hi,
It’s looking like Google is up to no-good. I started noticing streaming video bit-rate issues a couple of months ago so I looked into the reason why. Eventually I discovered that changing the user agent string from the default FireFox to Chrome cured the the issue. Checkout this video I recorded where Google appears to be throttling streaming bit rate base on the web browser you use.
I filed this bug with Mozillia:
It gets even weirder! Checkout this excerpt from a followup comment I left.
Hi,
I have been putting all of this together at least on the account throttling side. Google is throttling my YouTube streaming based on my account (see above). The reasons are not entirely clear but what is clear is one of Googles apparent goals. I have a pretty unique situation as far as digital access goes. I live way out in a rural area and am pretty much dependent upon cell phone base access to the internet. But, I also have a very slow (Geo-location reasons) but available DSL connection to compare with when needed. This gives me some variety and options to access the internet.
Google will display a “Experiencing Interruptions?” pop-up link on videos that are excessively buffering a stream and clicking on that pop-up link will open a web page displaying connection information, like your current ISP, a graph of past video view traffic for that ISP and more. The ’ graph of past video view traffic’ is of note because it so closely parallels (pretty much exactly) the times I experience streaming bit-rate throttling when logged into my Google account. The upshot here is Google appears to be throttling the streaming bit-rate for a YouTube video to match the traffic experienced at the ‘last mile’ ISP connection point based on history and not actual conditions as logging out of my Google account stops the YouTube bit-rate throttling and videos stream at the actual ISP’s maximum bit-rate.
So obviously, based on my account, Google knows who my ISP is, when the high traffic times are and how much and when to throttle video to match the ISP’s traffic pattern. Throttling during these times is not likely to be noticed and could be even justified as some kind of efficiency. But it’s not, because logging out of my Google account stops the bit-rate throttling exposing the local ISP (and YouTube) as capable of streaming at a much higher rate.
I have a second DSL connection and while staying logged into my Google account and only switching from my tethered cell connection to a DSL connection the YouTube bit-rate throttling will cease. This is also further evidence of throttling YouTube stream bit-rate based on the ISP connection/Google account as the DSL connection is less likely to experience traffic condition (in my area) that support masking YouTube stream bit-rate throttling.
All of this is easily reproducible worth a look into.
So. I could use some help verifying some of the above. If this pans out to be true for others, not cool.