Does Port Forwarding Require a Public IP Address?

Modem Combo Units:
Couple of options,
1. Configure the modem for transparent bridge mode. Then use the Orbi router in router mode. You'll need to contact the ISP for help and information in regards to the modem being bridged correctly.
2. If you can't bridge the modem, disable ALL wifi radios on the modem, configure the modems DMZ for the IP address the Orbi router gets from the modem. Then you can use the Orbi router in Router mode.
3. Or disable all wifi radios on the modem and connect the Orbi router to the modem, configure AP mode on the Orbi router.

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KarenPetersenSu wrote:

I am stuck in a three manufacturer vortex and do not have the technical skills to navigate towards a solution. I am trying to connect a T-Mobile Cell Spot (mobile signal booster) and am receiving error lights indicating that I am not connecting with the Internet TMobile says I need to ensure ports UDP500, UDP4500 and UDP123 are open. Orbi tech support insists that since my ip address is private, port forwarding cannot occur AND that the problem is that my Time Warner/Spectrum dual router/modem is not bridged. Time Warner/Spectrum says many different things: 1) they do not issue public IP addresses because they are not safe 2) my modem IS properly bridged - and they reset it just in case, 3)ip addresses don't change 4)the issue is with ORBI, not them.

I was able to do the set-up for two of the three ports required (UDP500 and UDP 4500) but ORBI said it didn't really go through since I have the private ip address. When I tried to do the port forwarding for UDP123, I got an error message saying that port was already assigned.

Meanwhile, my T-Mobile booster is not connecting to the internet.

 

HELP!

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