Mainland Chinese get round the firewall by using virtual private networks
Many mainland Chinese use VPNs to obtain information, protect their communications or hide their real identities from internet snoops
China has developed a huge parallel internet sheltered by an electronic firewall known as the Great Firewall of China which blocks, filters and slows traffic on the internet. This significantly obstructs and impacts business, foreign trade and academic, social and cultural exchanges. However, virtual private networks (VPNs) have allowed Chinese web users almost unimpeded access to the internet with the additional benefit of anonymity.
IT professionals there are among the heavy users of VPNs simply because they know how to do it, and because techie sites such as Github are blocked by the firewall, as are chats on Twitter and file sharing on Bittorrent.
Technology companies such as Tencent give all employees full access to the internet. In early 2010 Agence France-Presse reported an estimated 150,000 Twitter users in China. Paradoxically, whereas in the US or Europe one is more likely to hear people say that they can only access Facebook at home because it's censored at work, in China, you are more likely to hear people say, "I can only access Facebook at work" because it's censored at home.
VPNs work by encrypting and anonymising data traffic between computers, so that neither the content, sender or destination of data packets streamed over the net are readable by the firewall. Businesses routinely rely on this resulting anonymity for secure communications, as do hackers for hacking, software pirates for file sharing, porn aficionados for viewing porn, academics for collaborating on Google docs, mass online gamesters for gaming, gamblers for gambling, organised criminals for hiding their identities and dissidents for reading, commenting and "spreading rumours" .
VPN hides your real Internet Protocol (IP) address. If you are in China and connect to a VPN server in another country it substitutes your IP with another IP address from that country, so that you can view online TV, books or other content normally restricted.
If you visit China often you will be concerned about keeping in touch with the world via social media. If you have offices with a broadband connection in the mainland and Hong Kong you can set up a secure VPN between the places.
