These are the instructions for one type of Verizon FIOS Internet modem/router/hardware firewall.
Open your Internet browser and type the following in the Internet address blank: 192.168.1.1
That will cause communication with your hardwall firewall. (Some hardware firewalls require a different address.) Then you will be prompted to enter your user ID and password. If you don't know this, contact your Internet provider for that information.
Then to stealth your firewall, do the following:
Click on the Firewall Settings icon toward the top of the page. Then it will give the warning “Do you want to proceed?” Then click on Yes. On the left side of the new page that opens, click on Remote Administration. Make sure that there are no checks in any of the boxes. I think by default there is a check in the box for “Allow Incoming ICMP Echo Requests (e.g. pings and ICMP traceroute queries)” before the firewall is setup for the first time OR when the reset button is pressed. With this box checked, the firewall will return a “ping” to a hacker, and then the hacker will know that you are on-line.