FRITZ!Box 6890 LTE Service - Knowledge Base

FRITZ!Box 6890 LTE Service

Using VPN software from another manufacturer in the home network

You can establish VPN connections to remote VPN servers (for example to the VPN server of your company) over the FRITZ!Box's internet connection, as well as VPN connections to a VPN server in your home network (for example the VPN server of a NAS system).

Note:Information on the necessary settings in the VPN solution being used can be obtained from the manufacturer.

Outgoing VPN connections

If you want to establish VPN connections to remote VPN servers, it is not necessary to configure any settings in the FRITZ!Box. By default, VPN passthrough is enabled in the FRITZ!Box for the VPN protocols IPSec and PPTP; additional settings are not required.

If the VPN software uses the IPSec protocol without NAT traversal or the PPTP protocol, the following restrictions apply when using it behind a router such as the FRITZ!Box:

  • It is not possible to establish more than one VPN connection to a given VPN server at the same time.
  • The IPSec operating mode "Authentication Header" (AH) cannot be used.
  • Normally VPN software does not receive notification when the internet connection is cleared and usually it cannot automatically renegotiate the VPN connection. The VPN connection must be renegotiated if the FRITZ!Box obtains a new public IP address when it re-establishes the internet connection.

Incoming VPN connections

If you want to establish VPN connections to a VPN server in your home network, you must share the ports in the FRITZ!Box that are required by the VPN server.

If VPN connections are set up in the FRITZ!Box, the FRITZ!Box uses UDP ports 500 (ISAKMP) and 4500 (NAT traversal). If the VPN server uses the same ports, either configure the VPN server so that it uses different ports, or disable the VPN settings in the FRITZ!Box under "Internet > Permit Access > VPN".

Note:You can find an overview of all of the ports opened by the FRITZ!Box under "Diagnostics > Security" in the FRITZ!Box user interface.