If using certificate to establish connection do not forget to export the cert from the Zyxel router and import into the VPN software client. The VPN software client must support certificate based authentication policy. You can also use a certificate to establish the VPN connection.
Authentication – Select "Pre-Shared Key" and enter a password for the VPN tunnel.
This is required to be able to establish a VPN connection between VPN software and the VPN router.
Verify support with the software manufacturer before creating the rule on the Zyxel router. This will depend on your VPN clients compatibility, not all clients support IKEv2.
A vulnerability has been identified, and those passwords can easily be decoded using software or online services. The client uses profile configuration files (.pcf) that store VPN passwords either hashed with type 7, or stored as plaintext.
added support for 64-bit versions of Windows Vista and Windows 7.
explicitly did not support versions of Mac OS X later than 10.5. The open-source vpnc client can connect to most VPNs supported by the official client. As with most corporate licenses, administrators are allowed to freely distribute the software to users within their network.
The software is not free but is often installed on university and business computers in accordance with a site-license.