The FRITZ!Box only supports VPN connections via IPv4. The FRITZ!Box does not support IPv6 VPN connections. However, using DS-Lite ("Dual Stack Lite") technology, VPN connections can also be established via an IPv6 internet connection.

You can use FRITZ!VPN, a smartphone, or other VPN software to establish VPN connections from a DS-Lite internet connection to a FRITZ!Box that is accessible at a public IPv4 address.

VPN connections between two FRITZ!Box networks (LAN-LAN linkup) are also possible if one of the two FRITZ!Boxes has a public IPv4 address. VPN connections from the FRITZ!Box on a DS-Lite internet connection to a company's VPN are also possible.

Only incoming VPN connections to a FRITZ!Box on a DS-Lite internet connection, for example with FRITZ!VPN or a smartphone, are not possible. However, the FRITZ!Box supports the new Port Control Protocol (PCP), with which VPN connections to the FRITZ!Box and other incoming IPv4 connections over DS-Lite will be possible. For this, the internet service provider must also support PCP. The first providers offering DS-Lite internet connections could support PCP in the course of the year.