We need to connect two offices together via a VPN. Each office has a static public IP address and runs NAT on the LAN side. There's also a need for a few people outside of these two offices to connect into either office to retrieve files. Is there a relatively simple to configure router I can put at each location that will both enable LAN to LAN VPN and allow people at remote locations in? And would the VPN client built into WinXP work or would the remote users have to install a proprietary VPN client? I'm familiar with the basic concepts of VPNs but have never implemented one before and don't know who makes good hardware and who doesn't.