Most VPNs support a configuration called ?split tunnels.? When a VPN is configured using split tunnels, traffic can get to both the Internet and to the VPN.
Early VPN implementations, in particular PPTP, limited access to one or the other; either you were connected to the VPN or you were connected to the Internet, but you couldn?t be connected to both simultaneously. The reason was that someone from the Internet could potentially bounce traffic through the VPN device onto the corporate network.
With newer implementations such as IPSec, this is not an issue, the IPSec device or client software will only route traffic from the LAN onto the VPN, not traffic from the Internet. So split tunnels are much safer. I would suggest checking your manual or on-line documentation for a reference to split tunnels to determine the specific configuration changes for your implementation.
All the best,
This was first published in August 2002