What is a VPN? Behind the initials VPN are three explicit words: Virtual Private Network. VPN is a virtual private network that establishes a secure connection, using for this a protocol of encapsulation.  This will transmit the data, as if you were using a virtual network cable between your machine and a server, without being “visible” on the entire network, and with interesting possibilities, including the change of your IP address .

A Virtual Private Network is a connection method used to add security and privacy to private and public networks, like WiFi Hotspots and the Internet. Virtual Private Networks are most often used by corporations to protect sensitive data. However, using a personal VPN is increasingly becoming more popular as more interactions that were previously face-to-face transition to the Internet. Privacy is increased with a Virtual Private Network because the user’s initial IP address is replaced with one from the Virtual Private Network provider. Subscribers can obtain an IP address from any gateway city the VPN service provides. For instance, you may live in   San Francisco, but with a Virtual Private Network, you can appear to live in Amsterdam, New York, or any number of gateway cities.

A VPN can take many forms. It can be integrated into a company firewall or provided as an online subscription service, which is a preferred option for individuals. Many suppliers exist, offering a variety of services that deserve careful comparison.

Several encapsulation protocols exist, and offer varying degrees of security. PPTP (Point to Point Tunnel Protocol) was invented by Microsoft. Its minimal security is preferred by more advanced protocols in this area, such as Layer 2 Tunneling Protocol (L2TP) or OpenVPN, which includes SSL encryption, which is used on most online VPN services.

Data encryption, on the other hand, has an impact on the performance of the connection. We can not have the security at the extreme and the maximum flow.

What uses for a VPN?
For private use, several scenarios can be envisaged. The most obvious is the circumvention of content restrictions that a service may apply to certain countries. Typical example: VOD services like Netflix and replay TV handle audiovisual rights that often can not exceed certain territories. Want to watch a show you missed on your favorite TV channel? It is not always possible from abroad without going through a VPN. Conversely, you can use this type of service to access content unavailable in France. Attention: the services concerned apply more and more often parries to prevent this circumvention.

More generally, the VPN is a way to bypass more severe restrictions such as state censorship. If you are traveling to China, for example, you will need a VPN to connect to otherwise inaccessible services. A VPN allows you to change your IP address and thus guarantee relative anonymity. VPN is also a way to access sensitive data by reducing the risk of information theft by hackers. Some antivirus vendors even offer VPN options for this purpose.

In business, the most common use of a VPN is to connect to your corporate network from any computer outside of it. No need for a third party service for this: the company directly manages the network and provides the identifiers to the employees. On the other hand, you may need a VPN service at your workplace to access content restricted by your business. But if you can have this occasional need, do not overdo it and respect the rules of your employer!