How should I configure firewall settings on WAN device (e.g., Verizon modem) to have Balance 20 be the firewall

Greetings All,
Network setup:
WAN1 (Comcast)
WAN2 (Verizon)
Balance 20
My LAN

Current Situation:
I have opened ports on the Verizon modem (actually an ActionTec modem/router) to allow desired network traffic on specific ports to be directed to the Balance 20. I have configured the Balance 20 to forward those selective ports to the target devices on my LAN.

Goal:
Have the Balance 20 manage all firewall rules and, specifically, to manage selectively opened ports for applications such as Windows Remote desktop without having to create rules on both the WAN devices and the Balance 20.

Questions:
Should I configure the Comcast and Verizon devices so that their respective firewalls are turned off completely, thereby passing the firewall functionality down the path to the Balance 20?
Is that the best way to do it?
Are there security concerns by doing this?

Please note, I have R most of TFM and I have searched this forum unsuccessfully. Any help will be greatly appreciated.

Thanks.

Hi,

There is no standard answer whether or not to disable/remain the firewall feature at the ISP router. Some may prefer to remain the firewall feature at the ISP router & some may think that maintaining multiple firewall is troublesome and they decided to disable the firewall.

Regarding to the security concerns, as long the outbound/inbound traffics is able to be control base on the firewall rules than i believe you are safe for any of the deployment.

Thank You