[phh]

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)

[privatelypublic]

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.

[whywhywhywhy]

> 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.

[gruez]

>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?

[ale42]

You'd probably need thousands of residential IP addresses to pass under the radar with so many SIM cards.

[preisschild]

There are bot nets that specifically offer such services

[privatelypublic]

This IS the botnet that offers the service.

[asah]

...and perfectly legal services too, e.g. joinmassive.com, brightdata, etc. (they're used for gathering listing data from e-commerce sites, job boards, etc.)

disclosure: I'm an investor/advisor in massive.

[privatelypublic]

Somehow, if you have to use residential proxies, its going to he a TOS break.

[mrb]

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.