Group 2 : 1024-bit Diffie-Hellman group. The larger the group number, the higher
the security.
Group 5 : 1536-bit is the third option.
This setting specifies the lifetime limit of this Phase 2 Security Association. By
default, it is set at 28800 seconds.
16.2 GRE Tunnel
Generic Routing Encapsulation (GRE) is a tunneling protocol that can encapsulate a wide
variety of network layer protocols inside virtual point-to-point links over an Internet Protocol
network. A GRE tunnel is similar to IPSec or PepVPN.
To configure a GRE Tunnel, navigate to Advanced > GRE Tunnel .
Click the New Profile button to create new GRE tunnel profiles that establish tunnel
connections to remote tunnel endpoints via available WAN connections. To edit the profiles,
click on its associated connection name in the leftmost column.