If the FRITZ!Box is connected to a remote network via VPN, the VoIP accounts (internet telephone numbers) entered in the FRITZ!Box can log into a SIP server in the remote network via the VPN connection. Calls can then be made to a SIP server via the VPN connection. However, we do not guarantee that this function can be used.

Important:Enter the IP address of the SIP registrar and not its host name when you enter the account information for the internet telephone number in the FRITZ!Box. The IP address must be from the VPN target network.