Port settings for 4/5G gateway

sbershtein wrote:

I guess I am confused.  This time last week i had my TP-link router (with virtual servers configured by port forwarding) hooked up to a Charter DOCSIS cable router and life was fine.  I treated my Spectrum assigned IP address as static, which it was for long periods of time.  If I were away from home and wanted to grab a file from the home location i would, remotely:  sftp -P 29457 Stu@97.81.60.225.  The odd port number used is to keep hackers at bay.  The 97. ip is my semi-static IP as assigned by Spectrum.  I have simply removed the DOCSIS router and substituted your router and no virtual servers.  Can someone make me smart as far as what is wrong?  Thanks in advance.

 

FYI, I am not affiliated with TMO. I am simply a TMO customer.

Your Spectrum cable modem supported bridge mode which allows your external router to get all unfiltered traffic from your public IP. On TMO 5G modems, there is no bridge mode so you can operate your external router as an access point or you can create a 2nd layer of DHCP. In either case, your external router on a TMO 5G modem will only see whatever traffic/ports that the built in router will allow which is the fundamental issue you are having.

There are no configuration options on TMO 5G modems other than wifi SSIDs and passwords. The other issue you will run into is that 5G public IP addresses can change on a daily, if not hourly basis just like a cellphone.