What Is Mobile Phone Verification and Why Do You Need It?
As technology evolves, so do security threats for businesses. More companies are falling victim to scams and breaches, putting their customers and reputations at risk. These incidents harm the user experience and can lead to lost business, brand damage, and serious legal issues. But there's good news. You can protect your company and customers with effective security measures. One powerful tool? Mobile phone verification. Let's explore how this simple solution makes a big difference in safeguarding your business.
What Is Phone Number Verification?
Mobile phone verification focuses on validating phone numbers at every stage of the customer lifecycle — including account creation, transaction authentication, and ongoing customer engagement activities — to decrease the potential for compromised security.
Two-factor authentication (2FA) is a common use for phone verification that benefits customers as well as businesses. With 2FA, you provide your password and another type of confirmation, usually a code sent to a verified phone number. This extra layer of security significantly reduces the possibility for unapproved users to hack accounts.
With billions of mobile phone numbers registered worldwide, the mobile phone number is a great way to verify user identity. It's a unique identifier that most people always have with them, making it both convenient and effective for security purposes.
How Does Mobile Phone Verification Work?
Mobile phone authentication is a very flexible security technology that can be used for several purposes. At its core, it offers an extra layer of security by asking for evidence that the user owns a particular number. Let's discuss the techniques and uses.
One Time Passcodes
This is the most widely used form of phone verification. Here's how it works:
A user attempts to sign up or log in.
They need to provide their phone number.
The system sends a time-sensitive code to that number.
The user needs to enter this number to validate their identity.
OTPs can be delivered via:
SMS: This is the easiest method and works with almost all phones.
Voice call: This option is helpful for those who prefer audio or have trouble reading text messages.
WhatsApp or similar messaging software: This provides another solution if you live in an area with a weak mobile signal.
SIM-Based Verification
This method verifies that the user's SIM card matches the phone number they've provided. It's particularly useful for high-security applications, as it's harder to spoof than OTPs.
Risk Reports
Some verification services provide detailed risk evaluations using phone number data. These reports can warn you of issues such as:
Newly ported numbers (which might be a SIM swap attack)
Numbers associated with or often used by scammers
Numbers with a history of fraudulent activity
This data helps enterprises make a more informed user account decision.
Ongoing Verification
It’s not just new accounts that require phone verification. For comprehensive security, it’s best to apply it throughout the customer lifecycle.
Password resets: Ensure only the real owner of an account can restore access.
High-value transactions: Create an extra safety precaution on big purchases or transfers.
Account updates: Enforce verification before approving updates of sensitive data.
Silent Authentication
Advanced systems can authenticate a phone number without an OTP and do so in the background. This makes verification safe and doesn’t create friction in the user’s experience.
Two-Factor Authentication (2FA)
Phone verification is a key component of 2FA systems. Users provide their password and then verify their identity via their phone, creating a robust security barrier.
The method you choose should fit your circumstances and strike the right balance between security and user-friendliness. Keep in mind that the aim is to secure your business without overcomplicating the process for customers.
What Can Phone Verification Check For?
Phone verification can offer tons of useful information for your business and customers. Here’s a breakdown of what phone verification might verify:
Fraud Risk Assessment
Verification services can evaluate a phone number and calculate a risk score, generally on a scale of 0–100, based on a range of factors, and then inform you of whether to grant, block, or report an account or transaction.
Current Possession
One crucial check is to verify that the user who owns the number actually has access to the number right now. This is to prevent fraudulent attempts on stolen or incorrect information.
Blocklist Status
Phone verification will compare the numbers to known blocklists, which contain numbers that are linked to scams, spam, or some other malicious activities.
SIM Card Changes
New SIM card changes can be a sign of trouble. Verification systems can even identify whether the number has been transferred to a new device recently, potentially indicating a SIM swap attack.
Network Information
The system can identify the phone's network carrier. Such data can be useful for spotting regional patterns or warnings of risk with specific carriers.
Phone and Line Type
Verification can determine whether the number belongs to a mobile phone, landline, or Voice over Internet Protocol (VoIP) service. There are risks and benefits associated with each type. For instance, mobile numbers are harder for fraudsters to acquire than VoIP numbers, as they are usually associated with a physical device and a particular individual.
Verification can also distinguish between prepaid and postpaid lines. Prepaid lines are sometimes considered higher risk as they're easier to obtain anonymously.
Number Validity
This simple validation can make sure the number is formatted correctly and theoretically possible in the chosen country code and area code.
Usage Patterns
Advanced systems can detect unusual usage patterns that might indicate fraud, such as a sudden spike in activity or use in unexpected geographic locations.
Number Age
Freshly created numbers might be flagged as higher risk compared to well-established ones.
Based on all these checks, phone verification forms a detailed risk profile for each user or transaction. This lets you make the best decision possible about how to handle different situations.
Why Is Phone Number Verification Important?
With nearly 90% of businesses losing up to 9% of their revenue to fraud, and $10 billion lost to fraud by consumers, verification has never been more important.
Besides the direct financial implications, misleading data makes decision-making difficult and results in misguided strategies. Verifying phone numbers helps businesses use accurate customer data to communicate better and tailor services to customers.
For consumers, phone verification provides another layer of security while engaging in online activities. It protects their accounts against fraud and identity theft. This increased security fosters trust and makes users feel more comfortable using digital channels and services.
In an era where data breaches are all too common, this added security measure offers reassurance and indicates that a company cares about its users.
Best Times To Use Verified Phone Numbers
Here are some user management best practices where mobile phone verification can increase security and boost customer acquisition and retention:
Authenticate registrations: When a new user registers for your application, phone verification can help authenticate identity, ensuring your new user is who they claim to be. This step also links the user and their device.
Authorize upgrades: Many applications employ a “freemium” model, meaning the basic app is free to use but a premium version can be accessed via a paid upgrade. Providing a message with a one-time passcode to verify mobile users and their intent to upgrade can help reduce mistaken or fraudulent downloads.
Reset passwords: When a user logs in to an app from an unknown or alternative device (i.e. with a different IP address than the one registered in their profile) and requests a password reset, sending a one-time passcode to verify the user’s identity can help reduce fraud and identity theft. For example, Gmail uses this process to verify your identity via your mobile phone number whenever a login attempt originates from an unknown device.
Reactivate users: When a user of an application or website attempts to sign in after a long period of inactivity, a mobile phone verification process can help ensure once again that your user is genuine and not a hacker or spammer.
Refresh user details: Changes in user profile information should always be confirmed with a simple message to the mobile device linked to an account. This step will verify the change. Ensuring that changes have been initiated by the account owner is not only essential for security but also for accurate information delivery to users. For instance, an airline can share important flight updates with customers only if they have current contact information.
Authenticate transactions: Confirming transactions with real-time communications significantly reduces costly fraud resolution. Requiring authentication of users at this critical moment via mobile phone verification is effective at reducing suspicious activity; that’s why many payment and ecommerce applications and websites require authentication of transactions with a one-time password sent via SMS.
What Are Security Alternatives to Phone Verification?
While some of these alternatives may suit specific scenarios, they all have negatives for applications requiring global access and a high level of security.
Passwords
You can always stick with the tried-and-true — except that passwords are tried and not-so-true. Their vulnerabilities are well known. Although hacker technologies and tools grow increasingly sophisticated every year, the easiest way to hack is still cracking the password. According to Finances Online, 81% of company data breaches are caused by poor passwords (this vulnerability is one of the reasons why mobile phone verification came about), while using a multi-factor authentication solution can block 99.9% of all attacks. Another factor to consider is that people are often overwhelmed by the number of passwords they typically need to remember, and they address this challenge by choosing dangerously common passwords that they (and hackers) will find simple to remember or figure out when they forget.
Biometrics
Using measurable human traits and characteristics — like fingerprints, faces, or voices — can be an effective way to verify a person’s identity. But these solutions are expensive and not yet universally adopted.
It's important to note that while biometric verification offers strong security, it's not foolproof. Biometric systems can show bias and inaccuracies, especially among minority demographic segments.
These biases can cause discrimination and security risks and therefore require the careful deployment and constant refinement of biometrics. Biometrics should be a part of an integrated security system and not used in isolation.
Social Network and Email Logins
These methods offer a number of attractions — there’s an increasing demand for social logins; they can relieve password fatigue caused by the hassle of having to reset an account; they’re mobile friendly; and more. But social logins can be hard to remember, not all customers are on social media, and such logins can be easily faked, resulting in bulk registrations.
Also, consider the risks involved with using third-party platforms for user authentication. If you rely on someone else’s infrastructure, you can’t discount the company changing its systems or policies. The latest example of this came in 2023, when X (formerly Twitter) redesigned its API access.
These changes disrupted numerous apps and services that used Twitter for user logins. Users suddenly had no access to accounts across several platforms because their Twitter-based authentication stopped working. This incident exposed the vulnerability of depending on external services to provide core functions such as user authentication.
ID Tokens
An ID token is a sort of digitally encoded signature that proves that the user has been authenticated. They are widely used to provide authorization and authentication to users when they access a website or a mobile application. But tokens come at an additional cost and are easily lost.
Mobile Phone Verification in Action
Want to learn more about how mobile phone verification can increase security and mitigate the risk of fraud and spam for your application or website? Let’s examine a real-world example:
Vinted, a popular online marketplace for pre-owned clothing, encountered problems with fraudulent purchases as the site evolved. The old methods of authentication proved insufficient or too cumbersome. To address this, Vinted implemented Vonage Verify API with two-factor authentication.
Key points from Vinted's experience:
They used SMS verification to identify fraudulent actions during the transaction process.
Only suspicious transactions required verification, ensuring no friction for the majority of users.
The system allowed Vinted to verify users rather than outright banning them, thereby minimizing false positives.
Vonage's pay-on-conversion model meant Vinted only paid for successful verifications, saving costs on fraudulent attempts.
The solution struck a balance between security, user experience, and cost-effectiveness.
As a result, Vinted could prevent fraudulent users from making transactions and make life easier for genuine customers. This case study demonstrates how mobile phone verification can combat fraud for growing online businesses.
Stay Secure With Vonage
As we've seen, mobile phone verification is an effective security solution — but it's only half the picture. To make sure your business and customers are truly safe, you must have a comprehensive security system.
Vonage offers a range of solutions to help you stay ahead of potential threats. Vonage Protection Suite is an integrated suite of solutions that provides complete protection for your company. Here are some of its key components:
Fraud Defender: An easy-to-use solution that detects and disables scam messages across SMS and voice traffic.
Verify API: Strong two-factor authentication for multiple channels, with customizable automatic failover options.
Number Insight API: Gain real-time fraud analysis data on any phone number globally with Vonage Fraud Score functionality.
Management APIs: Implement Vonage’s Report, Redact, and Audit APIs for compliance and security in your applications.
These are all available in separate or combined packages to create a tailored security solution to suit your needs. The Vonage Protection Suite helps you build a multi-layered fraud defense that safeguards your business and builds trust with your customers.
Take the next step today and protect your online presence while offering your clients the peace of mind they deserve.
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Still have questions about phone number verification?
If you need to verify a phone number for your business, set up a validation system that automatically sends a unique code by SMS or phone call to the number provided. Users can then type in the code as proof that they have access to the phone.
When asked to confirm your phone number as a customer, you will usually receive a short code by text message or phone call. Simply copy this code into the verification website/app in question. It checks that you can access the phone number you have listed as yours.
If you need to use an old phone number for the verification, your choices are limited. Typically, you will have to reach out to your old provider to check if the number is still in service. If it’s been assigned to someone else, you may be unable to recover it. It is usually recommended that you update your accounts with your current number for verification purposes.
