Your FRITZ!Box does not support combining several internet connections. Therefore, your FRITZ!Box cannot be used as a multi-WAN router to establish parallel internet connections via its integrated fiber optic modem and the WAN interface.

However, if you use an additional USB mobile broadband modem, your FRITZ!Box can establish the internet connection via the mobile network if the fiber optic or WAN connection fails (fallback). You can find information on how to set it up in the guide Setting up the FRITZ!Box for use with a mobile network.

Note:Only the FRITZ!Box 6890 LTE supports parallel operation via mobile and DSL or WAN internet access (for example via a cable modem). Downstream data rates of up to 600 Mbit/s are possible when combining LTE and DSL.