EarthX

About

At present, property titles are often paper-based, creating opportunities for errors and fraud. Title professionals find defects in 25% of all titles during the transaction process, according to the American Land Title Association. Any identified defect makes it illegal to transfer a property title to a buyer until it is rectified. This means property owners often incur high legal fees to ensure authenticity and accuracy of their property titles. Moreover, title fraud poses a risk to homeowners worldwide. US losses associated with title fraud reportedly averaged around $103,000 per case in 2015, compelling many property buyers to purchase title insurance. These title management issues could potentially be mitigated by using blockchain technology to build immutable digital records of land titles and using blockchain for transparent transactions. This approach could simplify property title management, making it more transparent and helping to reduce the risk of title fraud and the need for additional insurance.

EarthX mints its own tokens to represent the title to the properties. Before minting a token, it verifies property ownership using a zk-SNARKs created verification system which works without revealing specific information on the property. Once the token has been verified it is placed on a blockchain market place (OpenSea) for others to purchase.

Development environment:

Truffle v5.3.14 (core: 5.3.14)
Solidity v0.5.16 (solc-js)
Node v10.19.0
Web3.js v1.4.0

Deployment Info

The deployments can be seen on rinkeby.etherscan.io at the following transaction hashes:

> Network name:    'rinkeby'
> Network id:      4
> Block gas limit: 29970677 (0x1c950f5)

   'Verifier'
   ----------
   > transaction hash:    0x982d27d277387417e9f609cf47bf6767a2747f69d83c40582b63934f7b5e1d23
   > contract address:    0xbCbEeD3647A1A84Aa8aE1a167EF82C4aBAc58EC4
   > block number:        9011724
   > block timestamp:     1627414715
   > account:             0x1D3e665CE3C8a3004698dDE1F47c0016F3b24884
   > gas used:            967847 (0xec4a7)
   > gas price:           1.000000008 gwei
   

   'SolnSquareVerifier'
   --------------------
   > transaction hash:    0x6533e3fdfae46f3c61342c1133cd6977b511c13198959a466358f9cf06ac7988
   > contract address:    0xe4AFb5A33D1fA7978fc4A62112224F38c835A46b
   > block number:        9011725
   > block timestamp:     1627414730
   > account:             0x1D3e665CE3C8a3004698dDE1F47c0016F3b24884
   > gas used:            3739694 (0x39102e)
   > gas price:           1.000000008 gwei

Contract ABI

ABIs can be found in the built contracts. The SolnSquareVerifier contract that is already deployed on the Rinkeby network can be found in eth-contracts/build/contracts/.

Testing

The project has been built using truffle and can be tested easily with the following process:

Clone the repo: git clone https://github.com/maqzi/EarthX.git
Change directory: cd ./EarthX/
Install required packages: npm install
Change directory: cd ./eth-contracts/
Run tests: truffle test

The test cases should all pass. Other ways to test the tokens are mentioned below.

Mint script

The mint10.js script in eth-contracts/ has nodejs functions to mint tokens as the contract owner. Make sure to update the keys and contract addresses at the top of the script. This script can be used to communicate with the contract in absence of a Dapp.

10 initial tokens

The contract's tokens can be seen on etherscan along with other information on minting, holders and token transfers.

Opensea storefront

The storefront is located on testnet opensea which can be used to interact with the tokens.

Zk-SNARKs

A Zero Knowledge - Succint Non-interactive ARguments of Knowledge or ZK-SNARK is used to verify ownership of a particular asset it the real world before onboarding it into the blockchain as a EarthX token. For the sake of this experiment, the proof is made available in the zokrates/code/ directory

maqzi/EarthX