Network
Universal Plug & Play (UPnP) is used to provide connected computers with status information about the FRITZ!Box. This function must be enabled for FRITZ!DSL to display status information. It has no influence on the security settings of the FRITZ!Box.
Programs that support UPnP can be used to change security settings automatically, such as the FRITZ!Box port forwarding rules. For reasons of security, only enable this option if you really want to allow incoming connections from the Internet.