So I have found recently that there are certain places where certain blocked sites — Facebook and Twitter yes; Blogspot no — are still inaccessible even when I’m logged in through my VPN. This seems to happen most consistently when I’m connecting from cafes in the Jiaodaokou and Jinbao Jie neighborhoods of Beijing, over what I believe is Netcom ADSL, and it happens regardless of which Witopia gateway I’m connected through.

I’m not the techiest person, but from my understanding of the way VPNs work, this should not be happening. What’s extra-special weird about it is that when I run traceroute to find out where the connections are failing, it seems that the Great Firewall may not even be involved: I’m seeing connection requests time out at IP addresses that are not within China. (One time it was a FastWeb server in Italy; another time it was Korea Telecom; another time it was a UK service provider.)
This is not a problem with my VPN or my setup, as far as I can tell: these sites work just fine through a VPN on my home connection. It seems to be a problem with one specific Netcom office (I could be wrong, but I think it’s the same office serving both Jiaodaokou and Jinbao Jie; then again, I believe my home connection runs through the same office.)

To be honest, the real effect of this is probably a net gain in productivity, but I would still like to know what’s going on, since I can’t figure out how the GFW — if it is that — is messing with me. Does anyone have any theories?