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Comment by jstalin | Hacker News Reader

I have experienced exactly this on Comcast. Suddenly, about two months ago, Netflix and Hulu became terrible to watch. I thought maybe it was my cable modem, so I upgraded it and still no luck. So I signed up for a VPN service and tested watching Netflix and Hulu both on the VPN and off.

Sure enough, when on the VPN, I get the highest quality picture. When I disconnected the VPN, Netflix dropped down to about 500kbps. Terrible.

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An excellent test. If a VPN makes something faster, despite the fact that it adds overhead to the process, that seems like proof that it's being throttled.

Not necessarily. It might just be bypassing the congested route that everyone else on your ISP is using. Comcast and Verizon have had disagreements peering with Cogent, one of Netflix's ISPs:

http://gigaom.com/2013/06/20/verizon-that-peering-flap-about...

It's not throttling, but rather the peering points along the "best" route between Cogent and Comcast/Verizon are overloaded, resulting in lousy connections between them. Look at this traceroute hop from Comcast to Cogent I just recorded:

   7  he-0-10-0-1-pe03.111eighthave.ny.ibone.comcast.net (68.86.83.94)  21.377 ms  20.379 ms  19.387 ms
   8  be7922.ccr21.jfk10.atlas.cogentco.com (154.54.13.161)  67.126 ms  67.747 ms  69.083 ms

40 ms to go one short hop in, I believe, the same data center.

This popped up on NANOG today; apparently FIOS-Cogent and FIOS-Level3 are both hosed. http://mailman.nanog.org/pipermail/nanog/2014-February/06411...

Disagreements with Cogent? Well, I never....

I feel it's unfortunate there's likely a lot of people newer to or unfamiliar with the bandwidth market that will not fully grok this comment.

It's not being throttled. There is a peering dispute between netflix's CDNs and the ISPs. Netflix's CDN's don't want to pay for delivery to the ISP. Normally CDNs peer with each other for free if the balance in each direction is equal. The problem is that any CDN that delivers netflix is hugely unequal since it's a huge one way stream.

The ISPs could just eat the cost, and let it be delivered for free. Or Netflix's CDNs could just pay the peering fee. Or Netflix could use different CDNs.

The reason the VPN works is because it sends the data over a different CDN that isn't saturated because of the dispute.

At least that is how I understand it, but I'm not an expert (or even a novice).

Umm wait, isn't such a dispute exactly what we call net-neutrality? Consumers pay ISPs for internet access, and now ISPs also want money from websites that provide a service to the consumers. But filtering those websites until they pay the ISP to be let through is the opposite of net neutrality. If what you're saying is true and ISPs are asking Netflix (or subsidiaries) to pay them to be let through unthrottled, then this is indeed the net neutrality problem as the OP reports.

Not related at all. This is about how the low levels of the internet share connectivity.

Net neutrality is about stopping the ISP from artificially decreasing available bandwidth. These kinds of things adjust the real bandwidth available.

That isn't at all what he said, though.

Then I misunderstood. What did I get wrong?

Edit: Wait I think I understand. I messed up peering and ISPs, right? Because the CDN connects to the internet via peering, and they're charging money (which does make sense to me), not the ISPs.

Um, no. I (the consumer) pay for my bandwidth. End of story. Anything else is a violation of the pipes that run the internet.

Oh, and the even more galling part... when watching Hulu on regular Comcast (without the VPN), the shows average around 500-900kbps. When it flips over to displaying the commercials, it jumps to 8Mbps or more!

The ads are probably served from a different service / CDN / network.

This is actually not malicious at all. An individual ad gets served to many more people than any given show, and as a result they'll get cached closer to the destination. Still pretty obnoxious though :)

I had this exact same problem with Sonic.net in SF. It was miserable. Each time I called they would tell me everything was fine and that it wasn't on their end- ignoring all proof.

On the verizon topic, soon after they got rid of the unlimited data tier my speeds would drop significantly after I reached 200-250MB of data transfer, but when I cycled the power and updated the roaming the speed would go back to normal until it hit the 200-250MB again. It wouldn't surprise me at all to learn that this was done on purpose or that they're currently limiting streaming traffic.

Are you sure you don't mean GB instead of MB? Because 200MB is like one youtube video with some decent quality.

Oh definitely MB. It was miserable having to reset the phone every few minutes.

Phone? You mean your internet connection at home, not mobile data right? 250MB indeed sounds miserable.

Yes it was mobile phone data, I should have been more clear in the original reply. Looks like I can't edit it now.

I had no problems with data speed/cap before they phased out the unlimited tier. I was grandfathered in, but like I said, it was never the same. I primarily worked from the phone during that period and it was a constant struggle. Which is why it wouldn't surprise me if Verizon, across all of it's services, throttled traffic.

Interesting I have been watching Netflix more than ever but I havent had any problem. I'm also using Comcast in Atlanta I wonder if its based on region?

It's only tangentially related to region. Comcast bring all of Netflix's traffic onboard in NYC and their East Coast routing is handled in New Jersey. Their eastern seaboard routing is about the only area where they're not having massive internal issues. Both their Denver (Midwest) and Oregon (PNW) iBone routing centers are having serious capacity issues that are manifesting as packetloss, giant latency increases and generally shitty route-arounds in the hope that it'll relieve pressure.

Why does Comcast use so few peering locations? Why do they route packets from their network to a university in the same city across half a dozen states?

    Why does Comcast use so few peering locations?

Because its cheaper to build and maintain only a few hubs. It's also cheaper for them to only onboard traffic a specific centers. JFK is the big US routing hub for Cogent and has the benefit(?) for Comcast of being where all the other big US ISPs onboard Cogent traffic. This lets them collectively bully Cogent (and other providers) into paying higher access fees.

    Why do they route packets from their network to a university in the same city across half a dozen states?

I couldn't really say, likely its more related to what that university is paying for. I don't see any unis in Comcast's BGP announcement meaning they're probably going over Comcast's "Business" or "Corporate" network (higher priority traffic, same network). Comcast does not have very fine-grain regional routing, especially in the Midwest, so you'll see connections that cover a short LOS take a long path due to lack of routing

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