By Cao Siqi

Cyber security analysts on Thursday defended China's Internet management after an overseas VPN (virtual private network) company on Wednesday announced some of its users in China have been unable to use the service since an upgrade of the Great Firewall, China's Internet infrastructure.

Cyber services should observe the network governance of the country for safety, analysts urged.

Astrill claimed in a Wednesday notice that since this year, VPN protocols used on iOS devices, including IPSec, L2TP/IPSec and PPTP, are not accessible in China in almost real-time.

An anonymous service support employee said Thursday that only iOS devices were affected while other devices like Macbook worked fine as they use different protocols. 

"It is because of the Great Firewall upgrade, and unfortunately, we can't tell you the exact time [about how long it will last]," said the employee, adding that the company has other solutions.

Many iPhone users were shocked to find that they could not log into their Facebook and Twitter accounts although they have bought Astrill's VPN service.

Whether to block VPN services and how to block them are closely related to the country's ability of network governance, Qin An, a cyber security expert at the China Institute for Innovation and Development Strategy, told the Global Times Thursday.

"Authorities apparently cannot ignore those services as they affect our cyberspace sovereignty. For instance, a shortcut has to be blocked since it could be used for some ulterior purposes although it might affect others who use it in a right way," said Qin.  

A cyber security analyst previously pointed out that companies running a VPN business in China must register with the Ministry of Industry and Information Technology, and unregistered VPN service providers are not protected by Chinese laws.

A free VPN provider fqrouter also said on its official Twitter account on January 8 that the service of fqrouter has officially closed.

Separately, VPN Tech Runo announced on January 5 that many of its IP addresses and users in some areas with L2TP protocol have not been accessible in China since December 31.

"The Great Firewall is blocking the VPN on the protocol level. It means that the firewall does not need to identify each VPN provider and block its IP addresses. Rather, it can spot VPN traffic during transit and block it," one of the founders of an overseas website which monitors the Internet in China told the Global Times Thursday via e-mail.

In recent years, more and more Chinese Net users are seeking alternatives to surf the Internet outside the Great Firewall by using mirror websites or VPNs.

Some Astrill VPN users reached by the Global Times Thursday said that the firewall update has also led to a price increase of VPN services. One said Thursday that another VPN service he bought a week ago increased its price by 60 yuan ($9.6) Wednesday to 240 yuan per year.