"When firewalls were first introduced, they became a must-have in the network security strategy. This created a false impression that all internet security problems were solved with a firewall. VPNs were developed to resolve the issues firewalls didn't address and plug the holes they left in the network security. This created the illusion that when a VPN is in place, you don't need firewalls. This is incorrect. For example, VPNs cannot enforce security policies, detect malice or mistakes, and regulate user access. VPNs can only do what they were meant to do: keep communications private through encryption and disguising the network servers real IP addresses."
