Rather than doing something on the consumer (phone user) end, attack the violators. The technology enabling us to make phone calls can surely prevent hiding or spoofing of the source. Phone companies know who their customers are. Thus, a link is provided between the robo caller and the phone company. Make this information available to thje FTC who can then prosecute violators. I urge vigorous and severely punitive measures for violators - make the penalty greater than the potential profit.