Appendix C - VPNs
Common VPN Situations
VPNHere, a PC on the LAN behind the Router/Gateway is using VPN software, but the Router/Gateway is NOT acting as a VPN endpoint. It is only allowing the VPN connec- tion.
∙The PC software can use any VPN protocol supported by the remote VPN.
∙The remote VPN Server must support client PCs which are behind a NAT router, and so have an IP address which is not valid on the Internet.
∙The Router/Gateway requires no VPN configuration, since it is not acting as a VPN endpoint.
Client PC to VPN GatewayFigure 79: Client PC to VPN ServerIn this situation, the PC must run appropriate VPN client software in order to connect, via the Internet, to the
∙IPsec is not the only protocol which can be used in this situation, but the ADE-
∙Windows 2000 and Windows XP include an IPsec VPN client program. However, configuration of this client program for use with the
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