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    Has Spectrum started using CG-NAT?

    Scheduled Pinned Locked Moved Off-Topic & Non-Support Discussion
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    • wgstarksW
      wgstarks
      last edited by

      I just moved and had my cable internet disconnected for a few months until I could get spectrum to run their network to my new house. Just got everything reconnected this morning and it’s all ok but my SG3100 doesn’t get a public IP. I called Spectrum tech support and asked them to put the cable modem into bridge mode. Was told that modems don’t support bridge mode (only routers) and Spectrum no longer provides a public IP. I’m just not sure that the tech support person knows what they’re talking about. Couldn’t find any reference to this change via google.

      Is anyone using spectrum and still getting a public IP?

      Is it possible to access the modem settings locally and reconfigure?

      The only identification on the modem is EU2251.

      IMG_2472.jpg

      Box: SG-4200

      R 1 Reply Last reply Reply Quote 0
      • R
        rcoleman-netgate Netgate @wgstarks
        last edited by

        @wgstarks What is the IP your new Specturm service gave you?

        Ryan
        Repeat, after me: MESH IS THE DEVIL! MESH IS THE DEVIL!
        Requesting firmware for your Netgate device? https://go.netgate.com
        Switching: Mikrotik, Netgear, Extreme
        Wireless: Aruba, Ubiquiti

        wgstarksW 1 Reply Last reply Reply Quote 0
        • wgstarksW
          wgstarks @rcoleman-netgate
          last edited by

          @rcoleman-netgate
          172.74.64.1

          Box: SG-4200

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          • R
            rcoleman-netgate Netgate @wgstarks
            last edited by

            @wgstarks That's a public address.

            ab990867-108a-44e5-beca-df9e9d98cedf-image.png

            Ryan
            Repeat, after me: MESH IS THE DEVIL! MESH IS THE DEVIL!
            Requesting firmware for your Netgate device? https://go.netgate.com
            Switching: Mikrotik, Netgear, Extreme
            Wireless: Aruba, Ubiquiti

            wgstarksW 1 Reply Last reply Reply Quote 0
            • wgstarksW
              wgstarks @rcoleman-netgate
              last edited by

              @rcoleman-netgate
              Thanks. I thought all the 172 and 192 addresses were private. Glad that’s not right.

              Box: SG-4200

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              • R
                rcoleman-netgate Netgate @wgstarks
                last edited by

                @wgstarks The RFC1918 space of 172 is only 172.16.0.0-172.31.255.255

                CGNAT is a different range altogether: https://en.wikipedia.org/wiki/Carrier-grade_NAT

                Ryan
                Repeat, after me: MESH IS THE DEVIL! MESH IS THE DEVIL!
                Requesting firmware for your Netgate device? https://go.netgate.com
                Switching: Mikrotik, Netgear, Extreme
                Wireless: Aruba, Ubiquiti

                wgstarksW 1 Reply Last reply Reply Quote 0
                • wgstarksW
                  wgstarks @rcoleman-netgate
                  last edited by

                  @rcoleman-netgate
                  I guess now I just need to figure out how to get the dyndns package to update the cached IP.

                  Box: SG-4200

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