A virtual private network (VPN) is a mechanism in which portions of a network are connected via the Internet, but information sent via these channels is encrypted. The result is a "virtual network" which is also part of a larger network entity. This allows users to privately share internal information over a public infrastructure. VPNs are often used to connect geographically displaced offices together or back to a head office.

There are a number of different types of VPN's that we can construct for our clients:

1. Secured Protocols
2. Tunnels

These include the more traditional VPN protocols such as PPTP (Windows 98/ME) and the more modern IPSec protocols. These are designed to allow connections from point-to-point, roving addresses and dynamic setups without causing any lapse in security of communication.

The most secure and preferred method is the IPSec protocol. This offers an encrypted channel from the time the packet leaves your network until it enters your designated remote site and vice versa. This means that even if someone was able to intercept the traffic, they could not decipher it.

The older PPTP is able to be setup on client's request, but it is recommended to avoid it due to its age and related insecurities.

Tunnelling is a technique that is used to create a similar effect to a VPN, but may be on a temporary basis, or to fix issues that arise with existing network infrastructure. Cybersite is able to implement a range of tunnel strategies that suits the client's need. These include IP Tunnelling, GRE Tunnelling and SSH Tunnels.

The IP and GRE tunnels are a method of setting up a virtual pipeline between two different networks to alleviate the problem of protocol incompatibility. IP tunnels can be used to create a tunnel through a range of different network types so the connection seems transparent to the average user. GRE tunnels offer control over the traffic for PPTP based networks. Both these forms of tunnelling are quite useful in the right circumstances.

One of the most common and probably the simplest form of tunnelling however, is the ssh tunnel. This method uses the popular ssh software to setup a tunnel between two boxes across a number of networks. This is useful for piercing firewalls to allow ports through which may not otherwise be allowed.