As spam calls become more common around the world, carriers have been working on ways to validate authentic callers, so users can know when a call is more likely to be relevant. This is done through a couple of protocols called STIR (Secure Telephony Identity Revisited) and SHAKEN (Secure Handling of Asserted information using toKENs). T-Mobile was the first carrier in the United States to implement the standard into a capability called Caller Verified, and now, AT&T is joining the fray.
The second-largest carrier in the United States today announced that Call Validation Displays, its own implementation of the STIR and SHAKEN protocols, is available today. Availability is still somewhat limited, starting with Samsung Galaxy S10, S10+, LG V40 ThinQ smartphones. AT&T"s Digital Home Phone Service can also use the feature. AT&T says the feature will come to more phones over the next year.
One big limitation with this feature is that, in order for more numbers to be validated, all networks must implement the STIR and SHAKEN protocols and link their implementations together. As such, just because a number isn"t validated yet, it may not necessarily mean it"s a spam call. More numbers will be marked as valid as implementations go live over time.
Of course, this won"t necessarily guarantee whether a caller is trustworthy or not, and AT&T says you should still be careful and use your own judgment before answering a stranger"s call.