Caller ID Authentication May Tame the Scourge of Spam Calls

Originally published at: Caller ID Authentication May Tame the Scourge of Spam Calls - TidBITS

Two interlocking technologies that phone carriers began rolling out a couple of years ago are helping dramatically reduce unwanted calls from spammers and fraudsters, while giving law enforcement better tools to track those that remain.


If anything, our rate of spam has gone UP significantly the last couple of months. And the Caller ID values are usually forged. So it would be A Good Thing if this was actually fully implemented and working as proposed, but you can’t prove that by me.


What carrier? And do you ever see the little checkmark? Verizon and T-Mobile may be out ahead on this. Intra-carrier compatibility has to be in place by June, but it doesn’t seem to be there (or fully there) now.

1 Like

I’m on Verizon and have had an increase in calls the past few weeks. Same with spam emails on my Comcast account.

Most of them seem to be the “your car warranty has expired”. One day I was expecting a call, answered it and put it on speaker. My hands were full so I let it go through its spiel and finally a person came on the phone. They asked for my car info and I told them I assumed they’d know it since they knew my warranty had expired (I haven’t had a car warranty since 1992). He insisted he needed it. I called him a scammer. He was completely offended. :roll_eyes:

(I never answer “hello”, I just pick up and let them say something. Sometimes it’s actually someone I need to talk to!)

Oh - I have the Verizon call block and a free version of HiYa. I also have apps set to offload due to lack of space on the phone, and now and then I discover they’ve both uninstalled. But spam does get through them at times.



Fwiw, I’m on Verizon Wireless and my wife and I get hardly any spam calls. Maybe one every two months each (and I have my phone set to reject unknown callers so i really never notice.)

And our home landline service (Spectrum) is way better than it used to be, though lately we are getting quite a few more same exchange fake caller ID calls than we used to. Nomorobo captures much of the spam calls.

T-Mobile on the cell, and Consolidated Communications on the land-line. Many more calls on the landline, most of them marked as in-state/same-area-code. I have not seen the checkmark on T-Mobile.

T-Mobile user. I’ve actually noticed spam calls have been much less recently. I use to get ten or so per day. Now it might be one every other day. I do have Spam Likely calls silenced (dial #622#).

I checked my recent calls, and only about 10% have checks.

How do I know if my VoIP carrier will use STIR/SHAKEN? I understand that VoIP carriers might not be part of it.

I wonder whether this is deployed, or even deployable, outside the USA. Oh, yes. Wikipedia says that it’s deployable Internationally, and deployed in Canada. No ticks here from my UK mobile carrier.

I did a unscientific survey of friends on Facebook. 13 reported “more calls the last couple of months”, vs 4 who said “fewer”.

Same here. Used to get several a week, now almost none in a month. I’ve always given out my phone number very sparingly. Same with email. I often resort to Mailinator. I wish there were Mailinator for phones. :wink:

STIR/SHAKEN are extensions to industry-standard protocols (SIP for VoIP calls and SS7 for traditional calls), which are used world-wide. So it’s really just a matter of if/when the various telcos around the world decide (or are forced by law) to deploy them.

1 Like

I’m on ATT and I scrolled down my recent calls, to find a very few with the Check Mark. And those are known callers in my contacts, and on same carrier.

One thing that makes this frustrating is that CLECs (Competitive Local Exchange Carrier) might be able to get reciprocal income from calls coming into phone numbers they “own” and “terminate” to their own customers. So by authenticating calls and marking/blocking spam/fraudulent/spoofed number means they might lose income from others. (yes, CLEC and other lines/ISP/VOIP providers still pay/receive carrier fees). A good read on CLECs…

Absolutely. There’s some settlement involved, but the spammers don’t generate income per se for the carriers who handle the vast majority of the volume of those calls.

The industry document I link in the article says carriers with 100,000 lines or more will have to have STIR/SHAKEN in place by 30 June 2021. I would expect there are smaller VoIP providers who have less oversight and are a bigger part of the problem who won’t be subject until 30 June 2023 per that document.

But what this says to me is that a) the vast majority of unique originating calls will be covered by June. b) VoIP providers who aren’t covered by the mandate and haven’t updated will stand out more strongly making it easier for carriers to identify and pursue technical and legal action against them or their subscribers.

I should have noted in passing in the article that the visual presentation of Caller ID verification isn’t the only measure that it’s happening. Carriers and calls could be fully or mostly verified behind the scenes, and the carrier isn’t passing the signal to a phone that causes the verification message to display. So if 8 of 9 hops are verified, the carrier might use that for its internal management of whether it’s a spam call or not, but doesn’t pass through a 100% verified checkmark. I expect that is going to improve, too, though.

Verizon user. Yesterday I had my first call with a checkmark
I signed up for Verizon Call filter but today when I checked the app I was not subccribed and there was no way to do so
I get lots of spam. One tactic is to answer but make no sound for a while, then answer. Many spammers seem to have robots voice activated

Well, it is a brute force approach but I have every call not in my contacts go directly to voice mail. The spam calls almost never leave a message (the car warranty people do) and occasionally I miss talking to someone directly but going to voice mail isn’t a big issue for me. And, I am careful to make sure the people I want to talk to are in my contacts. If I am expecting an important call from someone where I don’t know their phone number, I turn this off temporarily. (iPhone, T-Mobile)


1 Like

GREAT article Hope it continues to gain support

While most comments seem to be Cell Phone based I want to report that my Comcast VOIP “wired phone” service is showing an occasional (v) indication
I need to use this feature to get a bigger screen TV set since Comcast shows Caller ID information on the display

But I’m afraid even a $225 million dollar fine won’t be enough. They need to get the DoJ to file criminal charges against them and their customers, seeking a shutdown of their business, confiscation of all assets, and jail time for their employees.

Nothing less than that will be enough to send the message that spam doesn’t pay.


silent.m4r is my ringtone. If someone calls me who is in my contacts and has ever called m, they have a ringtone assigned. If someone calls who is not in my contacts they have to leave a message and a number I can call them back on., If not, they do not get to talk to me.

Might not work for everyone, but it works very well for me, and I doubt I will change this even if there are never any more robocalls or spam calls. Phon calls are an interruption that I do not want and I’ve trained most everyone to send me an iMessage or SMS instead if they want me to see it.

And I am sure no rules will prevent the fake policemen calling for donations to possibly fake police charities while implying that it’s you’re obligation to support the police, or any other charity hucksters. If I could buy an iPhone with no ability to install a phone app, I would do it.

1 Like