Hi,
Please refer to the product documentation:
Understanding Network Extension
Configuring Network Extension
Parameter | Description |
Split routing mode | The data from the client to the intranet is sent to the virtual network card based on the system routing table for forwarding, and the virtual network card uses the virtual IP address as the source IP address of the data. The data destined for the local subnet is forwarded by a real network card, and the network card uses the actual IP address as the source IP address of the data. Therefore, network extension forwards only the data to the intranet. In the mean time, the virtual network card also forwards the data that does not destine for the local subnet. |
Full routing mode | All data accessing any resources is delivered to the virtual network card to forward the data to the virtual gateway. |
Manual routing mode | You must configure a static route to the intranet on the device. The client identifies the data destined for the intranet and forwards the data through the virtual network card. |
Configuration examples (manual routing mode specifically):
Web: Example for Enabling Remote Users to Use Internet Explorer to Access Enterprise Intranet Through Network Extension (User Name + PASSWORD Authentication)
Web: Example for Enabling Remote Users to Access Enterprise Networks over SSL VPN Tunnels Using SecoClient
Also, you can see the explanation in this link too.
Please let us know if you need more information.