When we set out to create Passport Prime, we knew we had to do more than just build a new operating system. We needed to address a long-standing issue: how to combine the convenience of wireless communication with the airgap-level security that defines our current devices. That’s why, from the ground up, we reinvented Bluetooth with a brand-new protocol called QuantumLink.

For years, Bluetooth has been the easiest way to connect devices. It’s convenient, familiar, and just about everywhere. But there’s always been that underlying discomfort. Many of us worry about what’s happening behind the scenes, what if attackers can eavesdrop or attempt to tamper with sensitive data? Or what if they insert unwanted additional commands? In our first and second-generation Passport, we answered that concern by using a QR code-based airgap. No wireless communications, and thus fewer avenues for attackers. It worked, but it reduces convenience, steepens the learning curve for newer users, and makes real-time updates and interactions impossible.

With Passport Prime, we refused to settle. We sought the security of an airgap combined with the freedom of wireless communication. We worked with the Blockchain Commons team to design a new protocol that would solve this problem once and for all. The result is QuantumLink, a system that offers the best of both worlds: it’s wireless, but it’s built to be almost as secure as an airgapped connection.

Here’s how it works. Passport Prime houses a dedicated Bluetooth chip, entirely separate from the security processor which runs KeyOS. All data that enters or exits the Bluetooth chip is already encrypted using a quantum-resistant encryption scheme.

What is Quantum Resistance?

Regular computers use bits that are like coins that must be either heads or tails. Quantum computers use qubits that, through the strange rules of quantum mechanics, can be in a special state that’s sort of like having the coin spinning – it has some probability of being heads and some probability of being tails until it’s measured. This ability to be in multiple states at once is what gives quantum computers their unique capabilities.

Today’s encryption is like having a huge combination lock that would take regular computers millions of years to crack by trying every possible combination. But quantum computers could potentially solve these combinations much faster using specialized quantum algorithms like Shor’s algorithm, which exploits quantum properties to find hidden patterns in numbers.

We achieve the quantum resistance via the following main properties:

• The private/public keypair is generated randomly on each Passport Prime device just before you start the onboarding process
• The private/public keypair is based on CRYSTALS-Kyber rather than ECC to gain quantum resistance for the main keys
• The public key is provided to Envoy out of band via a QR code, which means the Bluetooth chip cannot see the value
• Every message sent over QuantumLink from that point on uses a unique ChaCha20-Poly1305 encryption key (ChaCha20-Poly1305 is considered quantum-resistant)
• This symmetric encryption key is, itself, encrypted using the recipient’s public key and an ephemeral public key from the sender.

The CRYSTALS-Kyber Key Exchange Mechanism is the most important part of QuantumLink’s quantum resistance properties. CRYSTALS-Kyber uses math problems that are hard even for quantum computers to solve – specifically, it relies on the difficulty of finding particular patterns in multidimensional lattices (think of trying to find a specific point in a vast, complex crystal structure). Even if a powerful quantum computer came along, it wouldn’t be able to crack CRYSTALS-Kyber’s mathematical puzzle any better than a regular computer.

This means the Bluetooth chip cannot understand any of the information it relays. It can only receive and send already-encrypted messages, and KeyOS will only accept properly signed messages. All other messages, regardless of who sends them are instantly ignored and dropped.

Even if the Bluetooth chip was malicious, it would not be able to extract any usable data nor insert any malicious commands.

Setting up Passport Prime with QuantumLink is as simple as scanning the QR code shown on Passport Prime’s screen during initial setup. This QR code contains Passport Prime’s public key.

Once scanned from Envoy, it sends its public key (encrypted) to Passport Prime over QuantumLink, and a fully encrypted tunnel is created.

From that point on, every message flowing through QuantumLink remains under lock and key, making it impossible for an attacker listening in over the air or a malicious Bluetooth chip to decipher communications.

The result is a Bluetooth-based protocol that provides a comparable level of security you’d expect from an airgap, all while offering the real-time convenience and flexibility. With QuantumLink, you can comfortably use wireless connections to interact with your phone, update KeyOS, and explore a world of new features all without compromising on security.

In addition, KeyOS offers a quick way to turn QuantumLink on and off, completely powering down the Bluetooth chip, making any communication impossible.

We’re excited to share QuantumLink with you as part of Passport Prime. It’s a bold step forward, one that redefines what you should expect from wireless communication. We’ve built it from the ground up to solve a problem that has nagged at us for too long: how to combine convenience and rock-solid security.

Now, with QuantumLink, the answer is finally here.