Specifying the Authentication for an L2TP VPN

For an L2TP VPN, specify the authentication by taking the following steps:

1. In the User Authentication area of the VPN pane for an L2TP connection, select the Password option button or the RSA SecurID option button as appropriate.
2. If the VPN uses a shared secret (a passphrase), enter it in the Shared Secret text box.
3. Select the Send All Traffic check box if you need to send all network traffic through the VPN connection.

The VPN pane for an L2TP connection lets you choose between a password and RSA SecurID for authentication. You can also use a shared secret for the connection and decide whether to send all network traffic through the VPN.

Choosing Whether to Route All Traffic Through the VPN

By selecting the Send All Traffic check box in the VPN pane, you can make the iPad or iPhone route all its traffic through the VPN once it has connected rather than just the traffic sent to addresses within the VPN. For example, with this check box selected, when Safari on the iPad requests a web page, that request goes across the VPN, out through your company's network connection, and back to the iPad the same way. The user gets the benefit (so to speak) of any proxying or filtering you've applied to your company's network connection, but performance tends to suffer because the data is taking a roundabout route and may go through several bottlenecks.

If you don't need to exercise this level of control over users, clear the Send All Traffic check box. Then, when an app requests information from the Internet, the iPad or iPhone sends the request straight to the Internet. When an app requests information from your network, that request goes across the VPN.