This firmware is the only way to solve the issue.
We need M2106B as spare parts for a quite old device designed by my company like 10 years ago. I have some modems but they do not have the right firmware for the device’ software. I don’t know why. The ones who designed the design have left the company. Nobody knows anymore. Investigating “why” would be way to costly.
If we can get this firmware, the modem could be replaced, the devices could be used a bit longer. If not, they’ll go to trash…