As far as we can tell, the Chinese government is blocking:
- VPN server IP addresses
- Websites owned by VPN providers
- Ports used by VPNs
- VPN download links
- VPN traffic
Also:
Chinese government uses DPI (Deep Packet Check) to block your OpenVPN traffic.
Personally, the WALL is also trying/learning to detect, “recognize” then interfer with your Chameleon as well. In my area, only some servers are not that slow and, stable (acceptable speed), some are almost unusable, even when it comes your Chameleon.
REF: Mortimer Rodgers@ Nintendo Power.