If your front door has an intercom system with an a/b port, you can connect it with your FRITZ!Box. Now the simple configuration can be performed in the FRITZ!Box user interface. When the doorbell rings you can simply use your telephone to speak with the visitor on an internal line and open the door.

As a counterpart to ISDN point-to-point connections, VoIP providers like sipgate and others are now offering SIP trunking. With this technology the provider places as many numbers as desired at the disposal of an IP-based telephone line, offering an economical communications solution for companies and small offices. With the new FRITZ!OS the FRITZ!Box supports SIP trunking. During configuration of an Internet telephone number you can enter not only multiple telephone numbers, but also the trunk number, the extension of the switchboard, and the length of the extension.