Scam telemarketers spoofing our NOC phone number for callerid

Scott Howard scott at
Wed Oct 6 14:26:21 CDT 2010

On Wed, Oct 6, 2010 at 8:55 AM, Jon Lewis <jlewis at> wrote:

> Some do.  Anyone with control of a phone system with digital lines (i.e.
> asterisk with PRI) can trivially set callerID to whatever they want. There
> are perfectly legitimate, and not so legitimate uses for this.

You don't even need the PRI.  There's a number of SIP providers that will
allow you to set CallerID.  In some cases they do some level of verification
first, but in many cases it's just a free-for-all.

There were some laws passed recently which makes "faking" caller-id illegal,
although I'm not sure exactly what the details are (eg, I'm fairly sure
sending your cell phone number from a desk phone is fine as you own both of


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