This is the documentation for the 21.07 version. Looking for the documentation of the latest version? Have a look here.

Step 1: Prepare for Deployment

Before the deployment can begin, it is important to gather all needed hardware, software, and parameters in advance.


  • Internet connectivity with a compatible ISP.

  • ISP CPE in routed mode (no NAT), bridged mode, or half bridge mode (PPPoE), if supported by the ISP and CPE.


    If the CPE does not support routed or bridged modes, then enable CPE features such as 1:1 NAT or “DMZ” mode mapping the external address of the CPE to an internal address to be used by TNSR. IPsec passthrough mode in the CPE, if present, can also be helpful if the CPE must perform NAT.

  • Create a reference diagram that shows the logical topology.

  • Review the TNSR Zero-to-Ping documentation.

  • A fixed (static) IP address for the TNSR outside interface.

  • Use NAT-T (traversal) support to configure a private IP the TNSR outside interface.

  • Management (web login, admin access) of the ISP modem.


  • IPsec tunnels work best on a fixed public IP address, changes to IP addresses require updates to configurations.

Reference Diagram

Create and maintain a reference diagram to support the deployment, as shown in the example below:

TNSR remote office reference diagram

TNSR remote office reference diagram

Remote Office Deployment Parameters

Define and document the deployment parameters for the initial remote office setup, as shown in the example below:

Base Deployment Parameters



TNSR Hostname


TNSR Outside Interface IP

TNSR Outside Public IP

Guest LAN Name


Guest LAN IP

Guest DHCP Range


Guest DNS IP,

Corporate LAN Name


Corporate LAN IP

Corporate DHCP Range


Corporate DNS IP,

In this example, the Remote Office is deployed behind an ISP cable modem performing NAT. TNSR uses NAT-T to float the encrypted traffic up to UDP port 4500. This ensures the external NAT device (i.e. ISP site modem/router) does not block the IPsec traffic.

  • TNSR Outside IP is different than the ISP Modem Public IP address.

  • ISP cable modem provides NAT for inside devices, which includes the TNSR outside interface.

IPsec VPN Tunnel Parameters

Define and document the parameters for the corporate IPsec tunnel and IP routing configuration, as shown in the example below:

IPsec VPN Tunnel Parameters



TNSR Outside IP

TNSR Public IP

IPsec Tunnel Peer IP

IPsec Tunnel ID


IPsec IKEv2 Crypto


IPsec IKEv2 Authen


IPsec Child SA Crypto


IPsec Tunnel IP

IPsec Tunnel Next-hop

Corporate IP Block