I'd like to correct your last paragraph. Most CDNs use anycast to send traffic to the closest POP they have to you. However, most implementations use DNS resp

I'd like to correct your last paragraph. Most CDNs use anycast to send traffic to the closest POP they have to you. However, most implementations use DNS responses for the front-facing servers. Not many companies outside of CDNs have the need or capital to use anycast for normal web/end-user traffic. There are several other scenarios where it can be your ISP or can cause significantly different timings between ISPs. A lot of ISPs offer a network internal forward caching system (CDN-like) so your traffic will appear to go directly from your ISP to the CDN. This is typically done with servers inside your ISPs network but with anycast routing so requests to the CDN outside of their network stay within it. I don't know if Google/YouTube does this, but I do know that Netflix does. Edit: this is independent of the post, which shows nothing but a fundamental misunderstanding of what's actually going on and why. I'd be more interested to see if this was flash or html5 video, whether it was using rtmp(s) for flash or http streaming, what IPs it ended up hitting instead of those two blocks and whether a traceroute for those two blocks went through the same or a different peer from where it finally connected.