On Mon, 30 Nov 2015 22:59:18 -0500, Mike Duffy
wrote:

On Mon, 30 Nov 2015 20:46:51 -0700, Don Y wrote:

Given that a caller can (not legally, in the US) spoof CID to report
*anything* they select (e.g., your own phone number)

Forget legality. How is it technically possible to spoof? I thought it was
all done by the telco equipment.

There are apps that allow you to send text messages that appear to
come from a different phone number from your own. I supppose you can
send them to yourself, for that matter.


If it's simply a matter of it being easy for foreigners, I suppose a
possible solution would be to block calls from outside the US & Canada. (I
put US & Canada together not for legal similarity, but because they use the
same 'International Country Code'.)

They do!? Maybe so.

Then we can use the adaptive spammer technique I saw on the news the other
night. I can't remember the telco, but one of the cell carriers offers a
phone app that lets you 'flag' callers as spammers, and you can set your
answering prefs to reject callers with a reported spam call rate above a
certain threshold.