Fast Internet connection, but slow video chat

Question

I am now in South Korea, which is reported to have the fastest internet. (It is kind of true, as it is quite easy for me to get a first post or get in a packed Hangout¹ on Google+. If this seems to be an ad for Google+, feel free to edit it out.)

The thing is, with this seemingly fast internet connection, I cannot have a fluent video chat with my friends in China, Japan, United Kingdom and United States.

Now I deal with it by dialing a VPN, and after this, the video chats (including 10 people's Hangout) become fluent.

I want to know where the problem lies, and how to deal with it. I do not like to dial VPN so often anyway.

_{1: Hangout is a group video chat for at most 10 people.}

Answer 1

A "Fast" internet connection does not necessarily indicate low latency, which is the most important factor in any real-time collaboration whether it be voice or video chat. Latency and bandwidth are two completely different beasts. This is why most corporate implementations of IP phones will make use of a prioritized "voice VLAN" to ensure calls are prioritized over regular LAN traffic. You can have a dedicated 50Mb connection and still have a choppy video chat with someone across the world. Give PingTest a try, see your results when running tests between the locations you've listed.

You may have a low latency connection to the VPN, and the VPN may have a better route to your friend's chat servers. The bottleneck could be between your ISP and the Google servers. A basic traceroute goes a long way in indicating bottlenecks between hops.

Answer 2

If you can fix it by using a VPN, then it is probably not your Internet connection speed, but you should still check that here to make sure. Your download speed may be stellar, but your upload speed not so good. The other side should do the same.

All that said, my guess is that there is something being either blocked, or a misconfigured router along the way, and when you use the VPN, you bypass it, so it works. I would call my ISP and ask them to troubleshoot it as it is probably beyond your control.

Answer 3

I see two possibilities here. One is a latency problem, and @John T already nailed that part in his answer.

The other is traffic shaping by your ISP. A dirty little secret of internet access is that for normal web traffic, 3Mb down/1Mb up is fast enough for most anything you want to do. You'll want faster speeds for large file downloads, p2p software, or if you're sharing the connection with other people, but for normal web browsing, e-mail, and even gaming and streaming video like youtube or netflix a quality 3/1 connection is plenty.

This is one reason why places like Korea are able to offer such high speeds... a lot of that bandwidth is sitting idle a lot of time. If you start doing something like simultaneous HD video uploads/downloads, plus maybe some other background traffic, your ISP's system may start shaping your traffic to prevent your connection from clogging their upstream connection to the internet for other users.