Privacy Protocol Overview

Understand ALIAS privacy features for anonymous virtual card creation

7 min read

Privacy Protocol Overview

The ALIAS Privacy Protocol is an optional feature that provides complete anonymity when creating virtual cards. Using advanced cryptographic technology, it breaks the link between your payment and the resulting card, making your transactions untraceable.

Advanced Feature

Privacy features require careful handling of secret recovery notes. Only use if you understand the tradeoffs and need complete on-chain anonymity. Most users don't need this feature.

What is Privacy Mode?

Standard Mode (Default):

You pay for a card with your wallet
The card is created immediately
Your wallet address is linked to the card in the system
Anyone can see your payment transaction on Solana blockchain

Privacy Mode (Optional):

You deposit funds into a shared pool with other users
Your funds mix with everyone else's funds
You withdraw anonymously using a secret note
Card is created with NO link to your original payment
No one can connect your deposit to your withdrawal

Think of it like putting your money into a jar with 100 other people's money, mixing it all up, then taking your money back out later. No one knows which money was originally yours.

Why Use Privacy Mode?

When privacy matters:

You don't want your wallet linked to your card purchases
You're privacy-conscious and want untraceable transactions
You're using the card for sensitive purchases
You want to break the on-chain connection between payment and spending

When standard mode is fine:

Speed is more important than privacy (standard is faster)
You don't mind your wallet being linked to purchases
You trust that merchant transactions are private (they are)
You're just testing the platform

Merchant Privacy

Standard cards are still private at the merchant level—stores see a Mastercard transaction, not your crypto wallet. Privacy mode adds blockchain-level anonymity.

How Privacy Works (Simple Explanation)

The privacy protocol uses something called zero-knowledge proofs—math that lets you prove something without revealing details.

The Simple Version:

Deposit: You send $100 to the privacy pool
Secret Note: System gives you a unique secret code
Mixing: Your $100 mixes with other users' deposits in the pool
Wait: More people deposit, making the pool larger
Withdraw: Later, you use your secret code to prove you made a $100 deposit (without revealing WHICH deposit)
Card: You get a $100 card anonymously

The Magic: The zero-knowledge proof proves you deposited money without revealing which deposit was yours.

Privacy Guarantees

What IS private:

Link between deposit and withdrawal (untraceable)
Your identity when withdrawing (anonymous)
Which card came from which deposit (unknowable)

What is NOT private:

Amount you deposited (visible: someone deposited $100)
That a deposit happened (visible on blockchain)
Number of people using the pool (public information)
Card usage at merchants (merchants see Mastercard transaction)

Understand the Limits

Privacy mode makes your ALIAS card creation anonymous. It does NOT hide your merchant transactions (those are private through normal card processing). It protects your blockchain identity.

Fixed Amounts Only

For privacy to work, everyone must deposit the same amounts. This prevents identifying deposits by their unique values.

Supported denominations:

$25: Testing and small purchases
$50: Good for general use
$100: Most popular denomination
$200: Higher value cards
$500: Maximum denomination

Why fixed amounts? If you deposit $73.42 and someone withdraws $73.42, it's obvious that's you. But if 50 people deposit $100 and someone withdraws $100, it could be anyone.

The Secret Recovery Note

When you make a privacy deposit, you receive a secret recovery note. This is the ONLY way to withdraw your funds.

What it looks like:

secret: a8f3d9c2e1b4f7a6d8c3e9f2b1a7d4c8e3f9a2b6d1c7e4f8a3b9d2c6e1f7a4d8
nullifier: c3e9f2b1a7d4c8e3f9a2b6d1c7e4f8a3b9d2c6e1f7a4d8a8f3d9c2e1b4f7a6d8

CRITICAL RULES:

Write it down immediately - The moment you see it
Save it securely - Password manager or physical paper
Never share it - Anyone with this note can withdraw your funds
No recovery possible - If lost, your funds are gone forever
ALIAS cannot help - By design, we don't store these notes

Lost Note = Lost Funds

Your secret note is NOT stored anywhere. Not on our servers, not in your browser, nowhere. If you lose it, your deposited funds cannot be recovered by anyone, including ALIAS. This is a fundamental security feature.

Privacy Pool Status

The privacy protocol is currently in testing phase on Solana Devnet:

Current status:

Deployed on Solana Devnet only
Fully functional for testing
Uses test USDC (no real money)
Limited number of participants

When will it be on mainnet? Privacy features will move to mainnet after thorough testing and auditing to ensure security.

Anonymity Set Size

Your privacy depends on how many OTHER people have made deposits:

Small pool (5-10 deposits):

Lower anonymity
Easier to narrow down which withdrawal is which
Still better than no privacy

Medium pool (50-100 deposits):

Good anonymity
Hard to link deposits to withdrawals
Recommended minimum before withdrawing

Large pool (500+ deposits):

Excellent anonymity
Nearly impossible to link deposits to withdrawals
Best privacy guarantees

Wait for More Deposits

For maximum privacy, wait for more people to deposit into the pool before withdrawing. The larger the pool, the harder it is to trace your transaction.