This tutorial walks through the necessary steps on setting up a L2TP/IPSec (PSK) VPN connection on Android's Ice Cream Sandwich (ICS) devices. There is nothing to download, thanks to the built in L2TP/IPSec client on Android IcS.

 

From the Android's settings menu, under Wireless and Network go to More... -> VPN -> Add VPN network 

 

Fill out the following settings under Edit VPN network:

• Name: We'll call it "Vpntraffic L2TP/IPSec" in our example, but it can be anything to help you remember the VPN connection.
• Type: Select "L2TP/IPSec PSK" from the dropdown menu.
• Server address: Refer to your welcome e-mail or client portal for your server's host name. Typically this will look something like us.vpntraffic.com, for example. ( not all server support l2tp/ipsec)
• IPSec pre-shared key :  vpn
• Tick the checkbox for Advanced options
• DNS servers: You can set this to use Google's DNS which is: 8.8.8.8
• Tap Save when finished

You should see your newly created connection listed under "VPN". Tap the connection name, and you will be prompted for your username and password. 

You should be back at the main "VPN" screen, and once the connection is successful you'll see a status of "Connected" under your connection name. The the connection name once conncted and you'll be able to see more details about your VPN connection status.