User's Manual

Chapter 7. Virtual Private Networking | 87
N600 Wireless Dual Band Gigabit ADSL2+ Modem Router DGND3700 User Manual
To set up a VPN connection, you must configure each endpoint with specific identification
and connection information describing the other endpoint. You must configure the outbound
VPN settings on one end to match the inbound VPN settings on other end, and vice versa.
This set of configuration information defines a security association (SA) between the two
VPN endpoints. When planning your VPN, you must make a few choices first:
• Will the local end be any device on the LAN, a portion of the local network (as defined by
a subnet or by a range of IP addresses), or a single PC?
• Will the remote end be any device on the remote LAN, a portion of the remote network
(as defined by a subnet or by a range of IP addresses), or a single PC?
• Will either endpoint use fully qualified domain names (FQDNs)? FQDNs supplied by
Dynamic DNS providers (see Using a Fully Qualified Domain Name (FQDN) on
page 161) can allow a VPN endpoint with a dynamic IP address to initiate or respond to a
tunnel request. Otherwise, the side using a dynamic IP address must always be the
initiator.
• Which method will you use to configure your VPN tunnels?
- The VPN Wizard using VPNC defaults (see Table 16)
- The typical automated Internet Key Exchange (IKE) setup (see Using Auto Policy to
Configure VPN Tunnels on page 110)
- A manual keying setup in which you must specify each phase of the connection (see
Using Manual Policy to Configure VPN Tunnels on page 117)
Table 16. Parameters Recommended by the VPNC and Used in the VPN Wizard
Parameter Factory Default Setting
Secure Association Main Mode
Authentication Method Pre-Shared Key
Encryption Method 3DES
Authentication Protocol SHA-1
Diffie-Hellman (DH) Group Group 2 (1024 bit)
Key Life 8 hours
IKE Life Time 1 hour
• What level of IPSec VPN encryption will you use?
VPN Endpoint Local IPSecID LAN IP Address Subnet Mask FQDN or Gateway
IP (WAN IP Address
Table 15. VPN Tunnel Configuration Worksheet
Parameter Value to Be Entered Field Selection