How to enable the IPv4 firewall on your modem

Activating the IPv4 firewall on your modem is optional. When the firewall is enabled, the security of your network is enhanced, but some network functionality will be lost.
Modem Advanced Step 1-4

1.  Connect a device, such as a computer or tablet, to the internet through WiFi or using an Ethernet cable connected to your modem.

2.  Open a web browser and type into the web address field.

3.  Log in to the modem's online user interface (Modem GUI) using your Administrator Username and Administrator Password. Unless you have changed the default settings, you can find this information on the modem's sticker. Note that these are different from your wireless SSID and security key.

4.  Select "Advanced Setup."

5.  Select "IPv4 Firewall" in the left sidebar. 

6.  Follow the steps to set up the IPv4 firewall:

  • Step 1:  Enable/Disable stealth mode. Do not enable stealth mode unless you fully understand the impact.
  • Step 2:  Set the IP address or addressing type to which the firewall will apply.
  • Step 3:  Set the firewall security level.
  • Step 4:  Check/uncheck selections in the firewall table to allow or block different kinds of incoming and outgoing traffic.
  • Step 5:  When you're finished modifying the rules, click "Apply" to save your changes.
About "Stealth Mode": Enabling stealth mode prevents the router from responding to probing requests. The router will still answer incoming requests for authorized apps. Unexpected requests, such as ICMP (ping) are ignored. Do not enable Stealth Mode unless you understand the technical impacts.
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