What is an L2TP/IPsec?
L2TP (Layer 2 Tunneling Protocol) with IPsec (IP Security) is a very secure protocol and compatible with desktop and mobile devices. L2TP/IPsec features 256-bit encryption.
Android L2TP Client Setup
These screen-shots are in English version Android OS. If you use other language, you can still configure it easily by referring the following instructions.
1. Initial configurations (only once at the first time)
Start the "Settings" application on Android.
In the "Networks & Internet" category, open "Advanced" and tap "VPN".
Click the "+" button to create a new VPN connection setting.
A new VPN connection setting editing screen will appear. Input something string on the "Name" field (e.g. "sgp-1.opensvr.net" ), and choose "L2TP/IPSec PSK" in the "Type" field, and you have to specify either hostname or IP address of the destination L2TP VPN Server. You also have to enter the user-name, password and secret (pre-shared key) on the Android screen.
2. Connect a VPN
Click on the VPN profile you set up and tap "Connect" to start a VPN connection.
3. Connected to VPN
While VPN is connected, all communications will be relayed via the VPN Server. You can access to any local servers and workstation on the destination network.