On Networks N300RM User Manual - Manual (Page 82)

Virtual Private Networking
82
N300 WiFi ADSL2+ Modem Router (N300RM)
Set Up a Gateway-to-Gateway VPN Configuration
Two common scenarios for VPN tunnels are between a remote computer and a network
gateway, and between two or more network gateways. Gateway-to-gateway VPN tunnels
provide secure access between networks, such as a branch or home office and a main office.
A VPN between two or more VPN-enabled routers is a good way to connect branch or home
offices and business partners over the Internet. VPN tunnels also enable access to network
resources across the Internet. In this case, use gateways on each end of the tunnel to form
the VPN tunnel end points.
Set the LAN IPs on each modem router to a different subnet and configure each correctly for
the Internet. The following table shows an example.
Table 3. Gateway-to-gateway VPN tunnel configuration
Parameter Value to Be Entered Field Selection
Connection Name GtoGr N/A
Pre-Shared Key 12345678 N/A
Secure Association N/A Main Mode Manual Keys
Perfect Forward Secrecy N/A Enabled Disabled
Encryption Protocol N/A DES 3DES
Authentication Protocol N/A MD5 SHA-1
Diffie-Hellman (DH) Group N/A Group 1 Group 2
Key Life in seconds 28800 (8 hours) N/A
IKE Life Time in seconds 3600 (1 hour) N/A
VPN Endpoint Local IPSecID LAN IP Address Subnet Mask FQDN or Gateway
IP (WAN IP
Address)
Gateway_A GW_A 192.168.0.1 255.255.255.0 14.15.16.17
Gateway_B GW_B 192.168.3.1 255.255.255.0 22.23.24.25
The LAN IP address ranges of the VPN endpoints have to be different. The connection will
fail if both are using the default address range of 192.168.0.x.