I don't think it's as simple as people think - for example, simply make sure the person owns the CallerID. At what point in the call stream would that be validated? You have to think that, when a call is made through a typical VoIP provider, it is most likely passed through 10 carriers (through arbitrage long-distance, then IXCs, then tandem/CLLI/POI CLLI).
I believe a good step would be to simply let the FTC trace using the CIC code that all carriers send over the PSTN/traditional telecom network. That way, the FTC could track a particular call or number through all the carriers until it reaches the originating information. The FTC has the capability to do that now, and based on the number of subpoena requests I've received (about 10/day), they actively do it.
The problem is that the companies doing the "illegal" robocalling (business to consumer/DNC or TSR violations) are overseas. There is no way, IMHO, that it can be stopped as long as long-distance providers exist.
At one point we were doing around a billion calls a day by a customer that swore they had nothing to do with dialer. They mixed the traffic very skillfully, so they always kept their overall statistics just at the contractual limit.
Blocking repeated source numbers just means people start making up numbers. At that point, you can't really block things. You could perhaps get a score of the likelihood of a call being legit, and perhaps retroactively you could determine a bunch of calls had a high amount of dialer. But I don't think it's possible to find an algorithm that has a good-enough accuracy rate to do real-time blocking.
Of course, from a telecom perspective, I don't really care about the content of the call. I just want the avg duration to not be so low that other carriers get upset. To that end, simply making sure dialer customers don't hangup immediately seems to suffice.
You are exactly right. All the traditional means (like blocking a callerID) is far past it's useful time. The dialer companies are getting smarter as well. It's BIG business for them, so it's worth the money to figure out solutions.
Also, it's very difficult to error on the side of caution - you do not want to block a normal phone call, or your upstream will stop sending you calls and you lose money.
Typically, a dialer customer will hangup once an answering machine is detected (usually around 2 seconds into the call) - causing lots of short duration calls. What the dialer customer's are doing now, is simply holding the call open for longer, to raise their overall ACD. It's a tough game. The moment telecom carriers start caring about what the call is (call types, information in the call, etc) - they become liable.
Since implementing this about a year ago, I've had zero robocalls actually ring my home line. Previously I was getting 7-10 per week.
Implemented using Anveo call flow.
o All home calls go to voicemail without exception. We pick up if we recognize the voice or the caller. No one seems to mind except my mother-in-law. She's gotten used to it though. I've also noticed everyone below a certain age rarely uses voice.
o I've added every number with which I regularly interact to my cell address book. If a call comes in from an unknown number, it goes to voicemail without exception.
YMMV.
Being both a math and a tech person, I would like to do a cost and effectiveness study comparing the purely technical solutions from the contest with solutions like the above.
Not to mention such a restriction would break many applications that depend on the source caller ID being forwarded. Call forwarding applications, some 911 implementations, etc.
They all run different hardware and software, and can't even keep track of who owns what DIDs. During the average day there are several phone network outages throughout North America as certain sets of numbers become unroutable from certain networks. Carriers often end up sending CSVs and excel files with their latest updates around, frantically.
In this system, Caller ID is a fourth class citizen. No one can spare the time to care about it, no systems are standardized, and no networks are responsive in anything like the time you'd need to maintain a system that monitors what caller ID information is allowed to originate from what place.
Instead, the carriers look at aggregate stats, and if it's too bad, they raise rates, charge fines, or disconnect customers. Some companies take a hard line and just cut any customer off if they appear to have any dialer. Others don't want to throw away an entire customer for only one fraction of the traffic. So everyone dances this line, trying to jam as much dialer in as they can get away with.