The "Private Data" Attestation: Merkle Roots
This page explains how identity documents can be securely and privately checked and stamped on a blockchain and introduces the concept of a Merkle Root Hash.
Understanding Private Data Attestations
Think of it like this: When you get a document notarized, the notary doesn't keep a copy of your document. Instead, they create a unique seal or stamp that proves they saw the real document. The seal doesn't contain any of your personal information, but it proves the document was verified.
A Merkle root hash is like that seal, but even more secure. It's like a unique fingerprint of your document - but it's a one-way fingerprint. Just like you can't reconstruct a person from their fingerprint, you can't reconstruct your document from its hash.
The hash is only useful when paired with a special cryptographic proof document, otherwise it is just a random number. Proofs are generated when you want to prove a fact from the original document, allowing you to choose which specific data to reveal. It's like saying, "Here's my date of birth from my passport, and here's proof on the blockchain that Zipwire witnessed me with that very document."
How It Works in Zipwire
The Process
Document Submission: You provide your identity document to Zipwire
Verification: We verify the document's authenticity
Hash Creation: We create a Merkle root hash (like a digital fingerprint) of your document
Attestation: We attest to this hash on the blockchain
Proof Generation: When needed, you can generate cryptographic proofs to verify specific attributes
Privacy in Action
When we attest to your document's hash on the blockchain, it's like the notary putting their seal on a record of your document's fingerprint. The blockchain only stores this fingerprint, not your actual document.Later, if you need to prove something about your document, you can use a special cryptographic proof. This is like having a receipt that shows your document matches the fingerprint that was attested to, without revealing the document itself. It's similar to how you might prove you own a house by showing a deed, without revealing your bank statements or other private information.
Benefits
For You
Complete Privacy: Your actual document never leaves your control
Selective Disclosure: Prove specific facts without revealing everything
Universal Verification: The attestation can be verified anywhere
No Repeated Checks: Avoid going through ID verification multiple times
For Platforms
Trusted Verification: Can verify your information without seeing it
Regulatory Compliance: Meet requirements while respecting privacy
Fraud Prevention: Cryptographic proofs ensure data hasn't been tampered with
Common Use Cases
Age Verification
Prove you're over 18 by revealing the date of birth from your passport, without revealing any of your other passport information
Nationality Verification
Confirm your nationality without sharing your full name or address
Professional Credentials
Verify qualifications without exposing personal details
Proof of income
Show your salary coming into your bank account without showing any other lines from the statement
How to Get Started
Connect Your Wallet: Link your Ethereum wallet to Zipwire
Submit Document: Provide your identity document for verification
Wait for Verification: We'll verify your document
Claim Attestation: Add the attestation to your wallet
Generate Proofs: Create specific proofs when needed
Technical Details
For those interested in the technical aspects:
The Merkle root hash is created using a cryptographic hash function
The attestation is recorded on the Base blockchain
All attestations are viewable on EAS Scan on the Base blockchain
Learn More
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