@tom Tom, Thanks for the Saturday reply! I' know I won't be able to ping the device's IP from the internet, just like I can't ping my phone or any other cellular device. They're inside the carrier's NAT'd subnet. I get that. But I cannot ping any public ip FROM the device. At the end of that old thread, he shows the Voxl pinging 184.108.40.206 and getting a response. I still don't, after following all of the suggestions in that thread. Like I said, I can get a DNS response if I ping a hostname, just no response to the ICMP from the host. Things that might help me: Another SIM from a different carrier or (or carrier's reseller, as most of the IoT SIM providers tout using ATT, T-Mobile and Verizon's networks, but have their own APN's..) to try. I'm working on that. In the meantime, coming from my early beginnings jockeying Hayes modems from DOS 3.3 running a BBS (Bulletin Board System, the pre-internet way we communicated..) I'm familiar with the Hayes AT command set (or used to be..) so I'd like a document (that I can't find on the Sierra site) listing my modem's AT command set so I can dig deeper into this problem myself. The Tailscale VPN looks nice and may be the simplest route (at a cost, and once I can actually talk to the outside world with this thing..) but I'm linking to a good video for you guys to look at. This guy is pretty savvy, and what he's doing here works. Without a VPN I might add.. The reverse SSH tunnel is quite interesting. Worth a look.