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FCC Chair Wants Carriers To Block Robocalls From Spoofed Numbers (arstechnica.com)
An anonymous reader quotes a report from Ars Technica: The FCC in 2015 made it clear that voice service providers can offer call blocking tools to customers, but commissioners said at the time that more needed to be done about Caller ID spoofing. FCC Chairman Ajit Pai has now scheduled a preliminary vote for March 23 on new rules designed to solve the problem. "One particularly pernicious category of robocalls is spoofed robocalls -- i.e., robocalls where the caller ID is faked, hiding the caller's true identity," the proposal says. "Fraudsters bombard consumers' phones at all hours of the day with spoofed robocalls, which in some cases lure consumers into scams (e.g., when a caller claims to be collecting money owed to the Internal Revenue Service) or lead to identity theft." The proposed rules would let providers "block spoofed robocalls when the spoofed Caller ID can't possibly be valid." Providers would be able to block numbers that aren't valid under the North American Numbering Plan and block valid numbers that haven't been allocated to any phone company. They'd also be able to block valid numbers that have been allocated to a phone company but haven't been assigned to a subscriber. The proposal would also codify the FCC's previous guidance that phone companies can block calls when requested by the spoofed number's subscriber. The upcoming vote on March 23 is for a Notice of Proposed Rulemaking (NPRM), which means the rules won't take effect immediately. The FCC uses NPRMs to seek comment on proposals before issuing final rules.
There is a reason for businesses to spoof a number.
Let's say I own Bob's National Grocery chain. My internal number is 888-555-1555. When I dial out, for privacy reasons, my number shows as the internal switchboard number - 888-555-2627 ("bobs" lol). This should not be a problem, as (1) my company owns this number and (2) it is answered. The issues here are two fold:
1. How do you determine the number I am advertising is mine? The answer here is simple - for numbers I advertise out from my phone switch, I must own these from the phone company I am peering with (first hop) or have some way to prove that I own those DIDs if I have multiple peering companies. Not a difficult hurdle to overcome.
2. How do you determine the number I am advertising (assuming step #1 is valid) is a valid company or answered number? In the case of robocalls or spam, my company could prove I own a block - satisfying #1 above, but turn out to be a voicemail box that's full or a non-company-answered blank DID.
About 15 years ago, I played around with a company owned phone switch setup and found that ANY number I put to advertise outbound was picked up and relayed to the target's caller id. I made a few test calls to my cell phone to validate that this was possible and then promptly reverted back to the company's owned block.
Karnal
As soon as they start blocking the obviously forged numbers, then all the spammers will switch to forging real numbers. Then they'll have to switch to routing-based blocking. If the number is assigned to a Verizon customer, and the call isn't being routed in a manner that Verizon uses, drop it.
Of course, this means Verizon customers couldn't use VoIP robo-callers with their own number, at least without registering it in some database first. Those customers wouldn't like the extra step, so they'll complain and block the rule.
What we really need is some unforgeable authentication system. This would require some trusted authority to give a public/private key pair for each phone number, so that each call would be accompanied by digitally signed Caller ID. For most customers, this would be handled transparently by their provider. Verizon and the like could even charge a fee for providing keys for use with VoIP dialers. Of course, this would be a major change in how calls are handled, so it would likely take many years and lots of equipment upgrades.