Everyone hates spam calls. The telephone network providers have banded together to create the “do not originate list“, which is essentially a blacklist that blocks some phone numbers from being used as outbound calls.
Why is the do not originate list needed?
Have you ever received a phone call where the caller ID claims the call is from the “IRS”? Or from your bank? Or some other reputable company? And then find out that it’s probably a scammer?
These spam calls are generally VOIP originated calls where the spammer manipulated the caller ID or the originating phone number to make you think they were someone else… someone legitimate.
VOIP phone systems and predictive dialers sometimes allow the originating phone number and caller ID of calls to be manually configured. The configuration is supposed to be used for legitimate purposes, but scammers misuse the setting.
How does the do not originate list work?
The do not originate list is a database of phone numbers of legitimate entities (such as the IRS, 911, banks, other governmental agencies, etc.) that are only used for inbound calls (terminating calls).
The database is then used to prevent outbound calls from being made using those numbers.
The database is checked by VOIP gateway service providers for all calls that are made using those numbers (or by spoofers claiming to be those numbers) allowing those spoofed calls to be blocked.
The do not originate list is a powerful tool against spammers, and in particular against this specific type of spam — spoofed calls that claim to be from legitimate entities.
Companies are starting to implement commercial do not originate registries as well.