Yeah, running your own switch allows you to send whatever you want as caller ID. You get the subject's number, call 911 and claim there's a hostage crisis.

I miss the days when prank calls were about refrigerators running. Things are so mean on the Internet these days. Trolls play for keeps, not for luls.

Sounds to me as if that telco infrastructure could do with a bit more security.

Caller ID is not and never was intended to be secure.