P2A Authentication for OEMs | Onboard Devices Without SMS OTPs

Introduction: Why OEMs Need to Rethink On-boarding

Did you know that more than 30% of device activations fail at the first step because users never receive their SMS OTP?

Sometimes it’s network delay. Sometimes it’s carrier filtering. Sometimes it’s just user impatience.

Whatever the reason, when your devices depend on SMS OTPs, the activation flow becomes fragile. If the OTP doesn’t arrive, the device doesn’t activate, and that means an unhappy customer right out of the box.

If you are an OEM launching devices at scale, this delay becomes a real business problem. That’s where P2A (Person-to-Application) Authentication steps in. It replaces SMS OTPs with network-driven verification that happens almost instantly.

In this blog, we’ll explore how OEMs can use P2A to simplify device on-boarding, reduce friction, and create a seamless “out of the box” experience for every user without relying on SMS OTPs.

1. The Real Problem: Why SMS OTPs Don’t Scale for OEMs

SMS OTPs were not built for global device ecosystems

SMS OTPs are convenient for apps, but they are unreliable when scaled across multiple countries, carriers, and devices.
For OEMs, that means thousands of users face delays or errors during first-time device setup.

Some users never receive OTPs due to carrier filtering. Others abandon the process halfway. Each failed attempt increases your cost per verification and activation, and affects your brand trust.

Here’s what typically goes wrong:

• SMS delivery delays due to carrier throttling
• SIM-swap or phishing attacks that compromise OTPs
• Cost of international OTP delivery
• No visibility into message failures

And when you’re shipping millions of devices globally, even a 5% failure rate is expensive.

2. How P2A Authentication Works (and Why It’s Different)

P2A flips the direction of authentication

Unlike SMS OTP, where the application sends a message to the user (A2P), P2A works in reverse: the verification is initiated by the user’s SIM or device.

This means the verification signal comes from the user’s phone number, making it inherently more secure and faster.
No OTP typing, no waiting for delivery, no chance of interception.

The P2A flow simplified

1. The user turns on the device or starts setup.
2. The device or SIM triggers a silent authentication signal to the OEM’s verification API.
3. The mobile network confirms that the SIM is active and matches the registered user.
4. The device gets verified automatically — no SMS OTP required.

The entire process takes seconds and works even in low-bandwidth regions.

3. Why OEMs Are Moving to P2A Authentication

A smoother activation experience

With P2A, users don’t wait for an OTP. The device activates the moment they connect to the network.
For OEMs, that means fewer support tickets, faster time-to-first-use, and higher satisfaction scores.

Better security and fraud prevention

Because the authentication originates from the SIM, spoofing and phishing attacks are almost impossible.
Each verification is tied to a real, active network identity.

Lower cost and operational efficiency

Every SMS OTP costs you money. P2A eliminates the need for sending OTPs altogether, saving significant cost per device — especially at scale.

Global reach and carrier compliance

Most major carriers now support network-based P2A authentication, allowing OEMs to integrate at a global level instead of maintaining hundreds of regional OTP routes.

4. Real-World Example: P2A in Action

Let’s take a real case.

A smartphone manufacturer wanted to improve device activation in regions where OTP delivery was inconsistent. By switching to a P2A verification flow, the company achieved:

• 98% activation success rate, up from 76% with SMS OTPs
• 40% reduction in customer support queries related to OTP issues
• 25% faster activation time per device

This change also helped them reduce SMS costs significantly and simplified their compliance operations.

That’s the power of moving from app-based OTPs to SIM-originated authentication.

5. How to Implement P2A Authentication as an OEM

Step 1: Choose the right partner and API

Select a provider that offers global carrier connectivity and ready-to-use APIs. You need a platform that integrates smoothly with your existing onboarding flow and supports device-level verification.

Get in touch with us to discuss your P2A needs today!

Step 2: Design your onboarding workflow

Embed P2A at the first boot or setup step. Allow fallback to app-based OTPs in markets where network-level verification isn’t yet available. 

Use analytics to compare how P2A and SMS OTP perform across regions.

Step 3: Track the right metrics

Monitor:

• Activation success rate
• Time to verify
• Cost per activation
• Fraud attempts post-activation

These numbers tell you where P2A brings the most value, and where to optimize further.

6. Common Challenges (and Simple Fixes)

Carrier and regulatory differences

Each region has unique telecom rules. Some carriers may not yet support full MO-SMS or SIM-based verification.
Work with a global provider that already has these relationships — it saves months of compliance effort.

Device and firmware compatibility

For non-SIM or WiFi-only devices, a hybrid model (P2A for SIM devices, OTP fallback for others) works best.

User consent and data protection

Always make the process transparent. Tell the user what’s happening during verification. P2A can be fully GDPR and CCPA compliant when handled properly.

7. The Business Advantage: Why P2A Is More Than Just Authentication

For OEMs, P2A isn’t only about user verification. It’s a business enabler.

• It reduces activation drop-offs, improving first-use experience.
• It cuts costs on global SMS routes and failed messages.
• It creates partnership opportunities with carriers for shared revenue on authentication traffic.

And most importantly, it gives OEMs full control of their device activation flow instead of relying on unpredictable SMS systems.

8. Future Trends in P2A Authentication

1. eSIM-driven growth

With eSIM adoption growing fast, P2A will become even more seamless — no manual entry, no waiting for any external message.

2. AI-based fraud detection

Machine learning models are being used to flag unusual device activation patterns in real time, making verification smarter.

3. Monetization opportunities for OEMs

Leading OEMs are turning their P2A verification traffic into new revenue streams by partnering with carriers that monetize network-initiated transactions.

Conclusion: The Next Step for OEMs

P2A authentication solves a problem every OEM faces — how to onboard devices fast, securely, and at scale.

By replacing SMS OTPs with SIM-originated verification, OEMs can:

• Speed up activation
• Reduce failure rates
• Save costs
• Strengthen user trust

If you’re ready to make device onboarding effortless, get in touch with our experts. Your devices deserve to connect right away. Let P2A make that happen.

FAQs

Q) Can SMS OTP still be used as fallback?

A) Yes, P2A can work alongside traditional OTPs for markets or devices that don’t yet support SIM-originated flows.

Q) How much can OEMs save by switching to P2A?

A) Depending on scale, OEMs save up to 50% in SMS delivery costs and significantly reduce failed activations.

Q) What does it take to integrate P2A authentication?

A) A simple API integration into your device setup flow. Get in touch with our experts at Message Central to discuss your P2A needs.