ChainFiles

Inspiration

In global trade and finance, documents are often required to be notarized and authenticated to prevent fraud. This is why the fraud detection and prevention market is worth $20 billion annually. Common documents that need notarization are commercial leases, articles of incorporation, contract, bill of sale, deed of trust, and more. But current offline notarization service doesn't go beyond borders.

Meanwhile, compelling blockchain use cases outside of DeFi are still elusive. However, digital notarization could be blockchain technology's other best use case because of its immutability nature and timestamping accuracy.

Introducing ChainFiles, a live and production-ready online notarization service powered by blockchain. You may use our site for free on the XDC mainnet by requesting free XDC tokens from us.

To implement this service on a blockchain, it's best to use a network that offers the cheapest gas fees and that is the XDC network. In fact, notarizing a document on ChainFiles with XDC costs less than 1 cent!

Since blockchain file notarization service is already available on Bitcoin, Ethereum, Solana, XRP, Avalanche, Hyperledger and more, XDC should have its own, especially when notarization is crucial for global trade and finance.

What it does

ChainFiles enables any enterprises or individuals to notarize their digital files. Notarization helps to prove that a document is authentic and unchanged since it was created.

We can store your files publicly or privately on XDC blockchain. For private file, we only store the hash string (SHA-256) of the file on chain to prove its existence. Because this file has cannot be deleted from the blockchain, it could attest to the file’s time of existence.

The hash string (e.g 0afda84dbfedf933df8ea5967….) contains a series of characters that are derived from your file and is unique only to your file. This method is called file hashing (aka file verification). If you edit even a single character in your original document, the hash value will change significantly. This prevents tampering with your file.

Hashing is a fundamental tool in digital forensic analysis and its use is admissible in court.

For public file, the entire file content is saved on the blockchain together with its name and description. This means anyone who could access the blockchain could read the file content.

This way we can attest to your original file and that it has not been tampered with since data on the blockchain is immutable.

Both private and public files are stored inside NFT tokens which are in your wallet thus attesting to your ownership.

How it works

You begin by creating a smart contract on XDC blockchain via our site. You shall own this smart contract as it is linked to your wallet. This contract allows you to store your digital files in the form of tokens called NFTs (non-fungible tokens).

This means all the NFT file tokens you create shall originate from this contract. The smart contract is tied to your wallet, not ours.

We shall pay for your gas. Our live site is free to use but if you need some tokens to pay for gas, please request from us.

When you uploaded a file, it shall be stored inside an NFT token created from your smart contract. Since the smart contract resides on the blockchain, we can verify the existence of your document from its timestamp on the blockchain.

The NFT file token actually contains a URL that links to your file content stored in a decentralized data storage network called IPFS (InterPlanetary File System). Since all files cannot be deleted in this system, your file will be kept permanently forever.

How we built it

We use the best and most commonly used hash algorithm which is SHA-256 (also known as SHA-2). It is considered more advanced than other algorithms such as MD5 and SHA-128.

In fact, this encryption algorithm is commonly used by cyber security and forensic experts and even your local bank.

SHA-256 algorithm is superior because it is collision-resistant. This means it's impossible to have two different files hashed with SHA-256 that would result in a similar hash value.

We can store your files publicly or privately on the blockchain. For a private file, we store the hash string (SHA-256) of the file on chain to prove its existence. Because this file has cannot be deleted from the blockchain, it could attest to the file’s time of existence.

The hash string (e.g 0afda84dbfedf933df8ea5967….) contains a series of characters that are derived from your file and is unique only to your file.

Hashing is a fundamental tool in digital forensic analysis and its use is admissible in court.

For a public file, the entire file content is saved on the blockchain together with its name and description. This means anyone who could access the blockchain could read the file content.

Why we choose to use MetaMask wallet

To reduce onboarding friction for new users, it's best to support the most common blockchain wallet in the world and that is MetaMask. We aim to support other XDC wallets in the near future.

FAQs

The complete FAQ is on our site.

Accomplishments that we're proud of

We're able to allow our users to deploy their own smart contracts without compiling any source code. In fact, they could name their own contract with their own symbol and the contract belongs to them, not us because each contract is linked to their wallets.

And to save you even more gas fees, you can notarize up to three files at once. This means the data for all the files are stored in one NFT token.

What's next for ChainFiles

This Web3 dapp is already live and we chose XDC to be our sole blockchain provider. If we win this hackathon, a portion of the rewards shall be used to pay for gas for our early adopters. By making this service absolutely free, it shall help to promote better adoption of blockchain technology outside its typical uses.

Also, we shall improve the UI to make the site more pretty!