The company I work for has 4 different office locations. At the moment interconnectivity is by using static ip's and over the internet. Every office has it's own domain and a server. I have found that company who was looking after IT infrastructure is so unprofessional that I might have to deal with everything myself. However I've found 4 packaged VPN capable NetGear firewalls which I would like to utilise at some point. Now, my question is: If everything works without VPN using internet and static IP's, will it continue to work next to VPN tunnel when I create one. Will I be able to set up a tunnel and than move some of the connectivity to use the tunnel partially, while keeping everything usable in the meantime?