Configuring VPNs, Setting the VPN Mode

Configuring VPNs

A Virtual Private Network (VPN) is a secure tunnel between networks or between a network and a user. The Gateway supports both network to network connections and network to remote client connections.

The Gateway supports IPSec tunnels, L2TP over IPSec, and PPTP connections and allows VPN pass-through to enable other secure devices on your network to set up their own secure connections.

Your Cable/DSL modem and your ISP must support IPSec pass-through, L2TP over IPSec pass-through or PPTP pass-through for you to be able to use these protocols.

See “The Virtual Servers Menu” on page 45 for details to configure pass-through protocols.

Setting the VPN Mode

The Gateway supports three modes of VPN operation:

■IPSec Enabled — IPSec (Internet Protocol Security) is a complex secure protocol with a variety of different encryption methods. When setting up an IPSec connection between two devices they must support the same encryption method.

■L2TP over IPSec Enabled — L2TP over IPSec is a combination of protocols which authenticates a user (using L2TP) and encrypts data (using IPSec). See “L2TP Configuration” on page 54.

■PPTP Server Enabled — PPTP (Point-to-Point Tunnelling Protocol) is an encrypted VPN protocol like IPSec. It is not as secure as IPSec but is easy to administrate. PPTP does not support Gateway to Gateway connections and is only suitable for connecting remote users.

Enabling IPSec VPN will disable pass-through to IPSec and L2TP/IPSec Virtual Servers on the LAN. Enabling L2TP over IPSec will disable pass-through to IPSec and L2TP/IPSec Virtual Servers on the LAN. Enabling the PPTP server will disable PPTP pass-through to a Virtual Server on the LAN. Pass-through outbound from clients on the LAN to servers on the internet is unaffected.

A VPN Tunnel needs the same protocol on both sides of the connection. If you are trying to establish an IPSec connection with another Gateway or with a user the other Gateway must support IPSec or the user must have software installed that supports IPSec VPN.

The VPN Mode menu is shown in Figure 51 below. Choose from the options by clicking in the appropriate radio button under VPN Server Setup.

IPSec Configuration

In the IPSec Configuration field, enter This Gateway’s ID as an Internet IP address or name of the Gateway that you are configuring. This value is common across all IPSec connections but does not apply to PPTP connections. If PPTP only is enabled, This Gateway’s ID field does not appear.

If you require main mode IPSec connections then this value must be the public IP address of the Gateway.