This method in one form or another is used for example by many companies to let employees remotely connect to the company’s secure network or for banks to establish safe channels for information flow. The usage of VPNs in one form or another is ubiquitous in a business environment, without which information flow would break down immediately. China is no exception to this. And in order to not interfere with all this, the Great Firewall of China just ignores VPN connections and lets any encrypted information pass through.
Now, there is of course nothing that stops a private user in China from using a VPN service to circumvent the Great Firewall of China, except of course for the $40 a year you have to pay for a regular VPN service and the fact that you need a credit card to pay for it… which is of course not “nothing” at all for the average Chinese. I would guess that less than 5% of China’s internet users have a credit card and are either willing or able to pay for such a service if they knew about it.
And this has worked out just fine for the censors in China. If you are so unhappy with the Great Firewall of China (and its not like people don’t know about it) that you are willing to use a credit card and pay for a VPN, then fine. Better than having a horde of upper middle class netizens getting up in arms.
But what if Google does leave China? Whats there to stop them from turning around and making available a free VPN for every Chinese netizen? That, the Chinese government would not like at all, however there is little they could do right away short of blocking all VPN connections and thereby instantly crippling the entire financial sector. Long term, however they could retry the failed and much hated Green Dam Youth Escort incident (more on that here).
Who really know what could happen. But for the heck of it, here are my top 3 scenarios:
1) The VPN service would only gradually catch on with a small fraction of internet users and the government would let it go just like they did so far.
2) Google suddenly widely publicizes their free VPN service, catching the censors off guard. The VPN gets downloaded millions of times before the censors can catch on and the file spreads like a virus. All efforts by the censors to contain the spread of the file prove futile.
3) Same as number 2, except in this scenario, some new form of the Green Dam Youth Escort program will be launched on a massive scale and something like a China-only Windows update will be released that removes Google’s VPN program from all computers.
Alas, this is just a thought experiment that will probably never see the light of day.