# USDT0 Network Documentation

> Official documentation for the USDT0 Network - omnichain stablecoin infrastructure built on LayerZero's OFT standard.

The USDT0 Network enables Tether-issued assets (USDT and XAUt) to move seamlessly across 30+ blockchain networks using a lock-and-mint architecture. All tokens maintain 1:1 backing with assets locked on Ethereum.

## Supported Assets

- **USDT0**: Omnichain USD Tether stablecoin (6 decimals)
- **XAUt0**: Omnichain gold-backed token, 1 token = 1 troy ounce of gold (6 decimals)

## Core Concepts

### Lock-and-Mint Architecture
1. Original assets (USDT or XAUt) are locked in the OFT Adapter on Ethereum
2. Equivalent tokens are minted on destination chains (1:1 backing)
3. Cross-chain transfers use LayerZero messaging
4. Redemption burns tokens and unlocks originals on Ethereum

### Security Model
- Dual-DVN verification: LayerZero DVN + USDT0 DVN must both confirm transactions
- Multiple security audits (Guardian, ChainSecurity, Paladin)
- Bug bounty program up to $6M on Immunefi

### Legacy Mesh (USDT0 only)
Connects existing USDT deployments (Ethereum, Tron, TON, Solana, Celo) to the USDT0 network via Arbitrum hub. Uses liquidity pools instead of mint/burn. 0.03% fee per transfer.

## Documentation

- [How It Works](https://docs.usdt0.to/): Architecture overview and supported assets
- [Developer Guide](https://docs.usdt0.to/technical-documentation/developer): Integration guide with code examples
- [Deployments](https://docs.usdt0.to/technical-documentation/deployments): Contract addresses for all chains
- [Security](https://docs.usdt0.to/technical-documentation/security): Audits, bug bounty, and security infrastructure
- [Legacy Mesh](https://docs.usdt0.to/overview/the-legacy-mesh): Cross-chain USDT liquidity network
- [How to Transfer](https://docs.usdt0.to/tutorial/how-to-transfer): User guide for transfers

## Key Addresses (Ethereum)

### USDT0
- OFT Adapter: 0x6C96dE32CEa08842dcc4058c14d3aaAD7Fa41dee
- USDT Token: 0xdAC17F958D2ee523a2206206994597C13D831ec7

### XAUt0
- OFT Adapter: 0xb9c2321BB7D0Db468f570D10A424d1Cc8EFd696C
- XAUt Token: 0x68749665FF8D2d112Fa859AA293F07A622782F38

## Developer Integration

All tokens implement:
- ERC20
- ERC20Permit (EIP-2612)
- EIP-3009 (Gasless transfers)
- LayerZero IOFT interface

Key OFT functions:
- `quoteOFT()`: Get transfer limits and expected amounts
- `quoteSend()`: Get LayerZero messaging fees
- `send()`: Execute cross-chain transfer

Transfer times: 30 seconds to 3 minutes depending on chain pair.

## Contact

- Integration support: integrations@usdt0.to
- Security issues: security@usdt0.to
- Transfer app: https://usdt0.to/transfer

## API

- Deployments API: https://docs.usdt0.to/api/deployments