January 17, 2024

RealNumber® DNO Safeguards Inbound Numbers from Fraudulent Calls

RealNumber® DNO Safeguards Inbound Numbers from Fraudulent Calls

Call spoofing ruins the reputations of diverse organizations, including small businesses, government agencies, and enterprise corporations. It also degrades consumer trust, which could prevent organizations from communicating critical information to people. For example, call spoofing could ruin the phone number reputation of a hospital, making it harder for them to communicate test results to patients.

Do Not Originate (DNO) lists have the potential to help rebuild trust by protecting inbound-only numbers from spoofing attempts. RealNumber® DNO stands out as a top option for organizations that want to safeguard their inbound-only numbers.

Benefits of DNO Registration

Ideally, STIR/SHAKEN would have made it impossible for criminals to spoof numbers. Those problems persist, though, as regulators attempt to close loopholes.

DNO registration adds your inbound-only numbers to a list that gets shared among service providers, regulators, and other organizations working with communications technology. When you register your numbers, it becomes much harder – nearly impossible – for someone to spoof them while placing outbound calls.

This is important because scammers were targeting highly publicized inbound numbers. Imagine that it’s tax season and the IRS has been advertising its taxpayer assistance services. As more people become familiar with the number they would call for help, scammers see it as an opportunity to trick taxpayers. Spoofing the well-known number becomes an easy way to trick consumers.

DNO registration would prevent anyone from using the IRS’s inbound-only number to place outbound calls, thereby blocking any spoofing attempts.

Protecting Vanity Numbers

Many organizations like vanity numbers because they’re easy to remember and foster brand awareness. Toll-free vanity numbers are also easy to expand nationally. As a business grows into other markets, it can keep using the same vanity number in new places. It might even use radio jingles, billboards, television commercials, and other advertising strategies to reach more people.

The factors that make vanity numbers beneficial also make them obvious targets for scammers. Consider a flower delivery business with the vanity number 1-555-FLOWERS. It would only take a little marketing and advertising for people to remember the number and associate it with the company. It’s so obvious that most people will remember it easily.

To a scammer, this looks like a great opportunity to take advantage of a phone number people know and trust. If they spoof 1-555-FLOWERS, many people will answer because they don’t want to miss a delivery.

As long as the florist only uses its vanity number for inbound calls – in other words, calls coming from customers to the business – it can use DNO registry to block outbound calls. Once registered, the number only works in one direction, so criminals can’t use it to place outbound calls to their targets.

Selecting a DNO Registry

There isn’t a central DNO registry, but there are three popular options used by most organizations: RealNumber® DNO by Somos, First Orion DNO, and ITG DNO.

RealNumber® DNO by Somos

RealNumber® DNO by Somos manages a list that currently includes more than 6 billion toll-free and local phone numbers. The comprehensive solution prevents fraudsters from spoofing registered numbers to place phone calls and send texts.

Somos’s essential role in managing communications infrastructure makes it an excellent organization for blocking spoofed phone numbers. Somos is a trusted company that helps manage the Reassigned Number Database (RNDA), Toll-Free Numbering (TFN), and the North American Numbering Plan (NANPA). It also supports over 1,400 service providers, creating reliable opportunities for Somos to distribute numbers on its DNO registry to providers across North America.

First Orion’s DNO

First Orion was the first company to launch a DNO registry. Its approach involves labeling numbers that have likely been spoofed. For example, if someone calls you from a registered number, your caller ID screen might mark it as “Scam Likely.” From here, consumers can determine whether they want to accept the call.


ITG’s DNO registry program prefers to focus on phone numbers from companies experiencing fraud. It might not block or label a spoofed number unless the spoofing surpasses an “active event-volume threshold.” ITG can, however, override this policy to protect organizations with spoofing threats that haven’t yet reached the threshold.

Fight Against Call Spoofing

STIR/SHAKEN authentication technology makes it harder for fraudsters to spoof the phone numbers of enterprises, government agencies, and small businesses. Unfortunately, it hasn’t yielded the results many hoped for. Registering your inbound-only numbers with a DNO helps fill STIR/SHAKEN’s gaps to safeguard your numbers and protect consumers.

If you have any inbound-only numbers, register them with a service like RealNumber® DNO. Otherwise, those numbers become ammunition for criminals who don’t mind damaging your reputation while they take advantage of consumers.

Monitoring Your Phone Number Reputation

DNO registries like RealNumber® DNO and STIR/SHAKEN call authentication help safeguard inbound numbers. Still, many businesses discover that they don’t have as much protection as they need. Their numbers, especially outbound numbers, still get flagged. Any number of factors could contribute to a warning label or flag. Dialing habits, for instance, can make numbers look suspicious to analytics engines.

We highly recommend registering your numbers with a DNO service. But you need an additional layer of protection that gives you real-time insight into your phone number reputation. Caller ID Reputation makes monitoring numbers simple so you can avoid the flags and labels that make consumers uneasy.

With Caller ID Reputation’s Device Cloud solution, you get screenshots from real devices connected to real service providers. If an issue arises, you can analyze the affected number and start rehabilitating it.

Would you like to learn more about how Caller ID Reputation can help you monitor your numbers? Start a free trial today.