That must be a significant difference to the Westell router as I don't see anything anyhwere about turning firewalls off or on or providing exceptions.
The Westell has a tab that says firewall settings and the only thing I can equate to your FW on or off is Maximum Security and Minimum Security. Max may be what you have as FW on as it severly restricts what outgoing ports a client can access. Min would appear to allow everything in and out. Typical (Medium) allows all out and nothing in except port forwarding - Medium is the default.
What I STILL don't understand is why my setup worked for >5-6 weeks and then spontaneously stopped working and also why no one at Verizon could tell me this might be the problem.
1. Good question. Maybe a new firmware update after the initial 5-6 weeks?
2. Because Verizon does not support port forwarding. They only support basic connectivity. If you computer can get on-line, they stop, no further support. Therefore their agents are not trained in everything the router can do and they probably on average know less about the routers capabilities than you do. Most of them dont even know how to get to the port forwarding section let alone how to configure it. There are exceptions but for the most part they know less about the router than most on these boards.