Secure Access: Firewall and Port Sharing

Protection from hackers and security for your own data – even in the factory settings, the firewall of the FRITZ!Box protects all connected network devices from unwanted data from the internet. Become acquainted with the FRITZ!Box firewall and find out how you can allow more leeway with port sharing on individual network devices.

Without you having to make any settings, the FRITZ!Box checks all incoming and outgoing data packets and automatically rejects unsolicited data (Stateful Packet Inspection). From the internet it is not possible to directly access your network devices, because these are invisible in the internet – this is guaranteed by IP masquerading or through Network Address Translation (NAT). Here an example:

To protect against what are known as ‘port scans’, all TCP and UDP ports on the FRITZ!Box are closed by default. If a network device should be reachable from the internet, port sharing must be configured for this device.

The Most Important Requirement

If port sharing is allowed, a ‘gate’ in the firewall is release for the selected device. Through this gate you access the network device directly from the internet. Similarly to a VPN connection, a public IP address is required for port sharing. Only if the FRITZ!Box can be reached from the internet can devices behind it be accessed through port sharing.