I am adding an Edgerouter Lite after my Comcast modem to better secure the home network. I will still have an external network directly attached to the Comcast modem. What is the best way to prevent access from the external network to the Edgerouter network and vice versa. Essentially, I would like for the Edgerouter to get internet access from the Comcast modem but limit access to / from the external network, while retaining the ability to access the router. Any thoughts?