Virtual private networks (VPNs) provide a means of accessing a private network over a shared public network such as the internet. Access to the private network is provided via an encrypted tunnel, and connecting to the network in such a way emulates a point-to-point link between the remote node and the network. Since the tunnel is encrypted, any packets that are intercepted are indecipherable without the encryption keys. Thus, VPNs provide a secure means of accessing a private network remotely.

Prior to the advent of VPNs, the only way of providing remote connections to a private network was through private WAN circuits. Private WAN circuits provide low latency, and in some cases, they may still be the best solution for connecting to a private network, but they also have high monthly costs. VPN solutions have grown in popularity, in spite of the fact that...