Comment by phh

5 months ago

I'm curious why they are using actual modems rather than just doing it with VoWifi that merely requires a SIM card reader (pretty much just an UART)

Among other things... having hundreds of calls and texts onramping from the same IP would be a rather large red flag.

I'm a little surprised that a behavioral analysis didn't flag these anyway. Probably did, just the networks don't care as long as they get their cut.

  • > networks don't care as long as they get their cut.

    Pretty clear this is the case, almost all of it could be stopped overnight with a simple whitelist to people you know and a blocklist of countries and regions where you’ll never ever need to take a call from.

  • >having hundreds of calls and texts onramping from the same IP would be a rather large red flag.

    Use VPNs? Surely paying for some subscriptions at $3/month is cheaper than renting an apartment in manhattan?

They do this so they are harder to track & block. If they were sending over Wifi then they have to hide the IP, so they have to use VPNs, which are often blocked, etc. But with their solution they have a standard SIM on the standard cellular network, so it's nearly indistinquishable from a regular cellphone.