# Frequently Asked Questions

### General Questions

#### What is OPN Chain?

OPN Chain is a high-performance EVM blockchain optimized for Ethereum compatibility. Built on proven Cronos technology, it offers:

* \~1 second block times
* 7 Gwei minimum gas price
* Full EVM compatibility
* Support for latest Ethereum features (Pectra)

#### How is OPN Chain different from Ethereum?

| Feature       | OPN Chain      | Ethereum       |
| ------------- | -------------- | -------------- |
| Block Time    | \~1 second     | \~12 seconds   |
| Gas Price     | Fixed 7 Gwei   | Variable       |
| Consensus     | Tendermint BFT | Proof of Stake |
| Finality      | Instant        | Probabilistic  |
| Compatibility | 100% EVM       | Native         |

#### Is OPN Chain decentralized?

Yes! OPN Chain uses a decentralized network of validators running Tendermint consensus. Anyone can run a full node, and qualified participants can become validators.

#### What is the native token?

The native token is OPN, used for:

* Transaction fees (gas)
* Staking (validators)
* Governance voting
* Network security

### Getting Started

#### How do I connect to OPN Chain?

1. Install MetaMask
2. Add OPN network:
   * Network Name: OPN Testnet
   * RPC URL: <https://testnet-rpc.iopn.tech>
   * Chain ID: 984
   * Symbol: OPN

See our [detailed guide](/iopn/developer-docs/getting-started/connect-wallet.md).

#### What wallets are supported?

Any Ethereum-compatible wallet works:

* MetaMask (recommended)
* Trust Wallet
* Coinbase Wallet
* Rainbow
* Hardware wallets (Ledger, Trezor)
* WalletConnect compatible wallets

#### How do I bridge assets to OPN Chain?

Official bridge coming soon! For testnet:

1. Get test tokens from faucet
2. No bridging needed for testing
3. Mainnet bridge will support major assets

### Development Questions

#### Can I deploy my Ethereum contracts?

Yes! OPN Chain is 100% EVM compatible. Your existing contracts work without modification:

```javascript
// Just change the RPC URL
const web3 = new Web3('https://testnet-rpc.iopn.tech');
// Everything else stays the same!
```

#### What development tools work with OPN?

All Ethereum tools are supported:

* **Frameworks**: Hardhat, Foundry, Truffle, Remix
* **Libraries**: Web3.js, Ethers.js, Viem
* **Languages**: Solidity, Vyper
* **Testing**: Waffle, Chai, Jest

#### What version of Solidity should I use?

Latest stable version (0.8.19+) recommended. OPN supports:

* All Solidity versions
* Pectra EVM features
* Latest opcodes
* Gas optimizations

#### How do I verify contracts?

Contract verification options:

1. Manual verification on block explorer (coming soon)
2. Hardhat verification plugin (when explorer launches)
3. API verification endpoints

#### Are there any OPN-specific features?

While maintaining full EVM compatibility, OPN offers:

* Faster block times (adjust timing logic)
* Stable gas prices (simplifies estimation)
* Instant finality (no reorg concerns)

### Transaction Questions

#### What is the gas price?

Fixed minimum of 7 Gwei. Benefits:

* Predictable costs
* No gas wars
* Simple estimation
* Fair access

#### Why did my transaction fail?

Common reasons:

1. **Insufficient gas limit**: Increase gas limit
2. **Nonce issues**: Reset MetaMask account
3. **Contract revert**: Check revert reason
4. **Insufficient balance**: Get more test tokens

#### How long do transactions take?

* **Average**: 1-2 seconds
* **Finality**: Instant (no confirmations needed)
* **No pending**: Transactions process immediately

#### Can transactions be reversed?

No. Like all blockchains, transactions are immutable once confirmed. OPN's instant finality means no reorganizations.

#### What's the transaction format?

Standard Ethereum transactions:

* Type 0 (Legacy)
* Type 1 (EIP-2930)
* Type 2 (EIP-1559) All supported!

### Node Operation

#### What are the hardware requirements?

**Minimum:**

* 4 CPU cores
* 16GB RAM
* 500GB SSD
* 100 Mbps connection

**Recommended:**

* 8+ CPU cores
* 32GB RAM
* 2TB NVMe SSD
* 1 Gbps connection

#### How do I run a node?

Quick start:

```bash
# Download binary
wget https://github.com/

# Initialize
./opn-node init

# Start
./opn-node start
```

Full guide: [Running Nodes](/iopn/developer-docs/nodes/node-overview.md)

#### Can I become a validator?

Yes! Requirements:

* Run reliable infrastructure
* Stake OPN tokens
* Maintain high uptime (99%+)
* Participate in governance

#### What's the difference between node types?

* **Full Node**: Validates transactions, serves RPC
* **Archive Node**: Stores all historical data
* **Validator Node**: Participates in consensus
* **Light Client**: Minimal verification (planned)

#### How do I monitor my node?

Key metrics to watch:

```bash
# Check sync status
curl localhost:26657/status

# Monitor peers
curl localhost:26657/net_info

# View metrics
curl localhost:26657/metrics
```

### Smart Contract Questions

#### Is Pectra supported?

Yes! Full Pectra support including:

* EIP-7702 (EOA account code)
* Transient storage (TLOAD/TSTORE)
* Memory optimization (MCOPY)
* All latest opcodes

#### How do I optimize for OPN?

Key optimizations:

1. Account for 1-second blocks
2. Use stable gas price (7 Gwei)
3. Leverage instant finality
4. No reorg handling needed

#### Are there contract size limits?

Standard Ethereum limits apply:

* Max contract size: 24KB
* Max transaction size: 128KB
* Block gas limit: 30M

#### Can I use OpenZeppelin?

Yes! All standard libraries work:

```solidity
import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
// Works perfectly on OPN Chain!
```

#### How do I handle errors?

Standard Ethereum error handling:

```solidity
require(condition, "Error message");
revert CustomError(param1, param2);
assert(invariant);
```

### Security Questions

#### Is OPN Chain secure?

Security measures:

* Byzantine fault tolerant consensus
* Slashing for misbehavior
* Regular security audits
* Bug bounty program
* Proven codebase (Cronos)

#### How do I secure my contracts?

Best practices:

1. Use audited libraries (OpenZeppelin)
2. Follow security patterns
3. Test thoroughly
4. Get audits for production
5. Monitor after deployment

#### What about private keys?

Standard Ethereum security:

* Never share private keys
* Use hardware wallets
* Secure key storage
* Multi-sig for large amounts

### Economic Questions

#### What's the token distribution?

Detailed tokenomics coming with mainnet. Testnet tokens have no value.

#### How are gas fees used?

Gas fees go to:

* Validators (block rewards)
* Network security
* Protocol development
* Community initiatives

#### Will there be staking?

Yes! Staking features:

* Validator staking (secure network)
* Delegation (earn rewards)
* Governance participation
* Slashing protection

#### What about inflation?

Inflation parameters:

* Controlled by governance
* Balanced for security
* Sustainable long-term
* Details at mainnet launch

### Technical Issues

#### "Cannot connect to network"

Solutions:

1. Check RPC URL: `https://testnet-rpc.iopn.tech`
2. Verify Chain ID: 984
3. Clear browser cache
4. Try different browser
5. Check firewall settings

#### "Insufficient funds for gas"

Solutions:

1. Get tokens from faucet
2. Check gas price (minimum 7 Gwei)
3. Ensure enough for gas + value
4. Try smaller test amount

#### "Transaction underpriced"

Set gas price to at least 7 Gwei:

```javascript
{
  gasPrice: '7000000000' // 7 Gwei in wei
}
```

#### "Nonce too high"

Reset account in MetaMask:

1. Settings → Advanced
2. Reset Account
3. Retry transaction

#### "Contract deployment failed"

Check:

1. Contract compiles successfully
2. Constructor parameters correct
3. Sufficient gas limit
4. Account has funds

### Integration Questions

#### How do I integrate OPN in my DApp?

Simple integration:

```javascript
// Just update your network config
const networks = {
  opn: {
    chainId: 984,
    rpcUrl: 'https://testnet-rpc.iopn.tech'
  }
};
```

#### Does Chainlink work on OPN?

Oracle integrations coming soon:

* Chainlink (planned)
* Band Protocol (evaluating)
* Native oracle solution
* API3 (considering)

#### Can I use Graph Protocol?

Indexing solutions:

* Graph Protocol (planned)
* Native indexer (in development)
* Custom indexing supported

#### What about IPFS integration?

Decentralized storage works normally:

* IPFS links in contracts
* Arweave integration
* Filecoin compatibility
* Standard patterns apply

### Mainnet Questions

#### When is mainnet launching?

Mainnet timeline:

* Q3 2025: Final testnet phase
* Late Q4 2025: Mainnet launch
* Follow announcements in Discord!

#### Will testnet tokens transfer?

No. Testnet tokens are for testing only and have no value. Mainnet will have separate distribution.

#### How do I prepare for mainnet?

Preparation checklist:

1. Test your contracts thoroughly
2. Audit critical code
3. Plan migration strategy
4. Join validator program
5. Stay updated in Discord

#### What happens to testnet?

Testnet continues running:

* Permanent testing environment
* New feature testing
* Developer playground
* Free tokens always available

### Community & Support

#### How do I get help?

Support channels:

1. [Discord](https://discord.gg/iopn) - Real-time help
2. Email: <info@iopn.io>

#### Can I contribute?

Yes! Contribution areas:

* Code contributions
* Documentation
* Community support
* Bug reports
* Feature suggestions

#### Are there grants available?

Grant program launching soon:

* Development grants
* Ecosystem grants
* Research funding
* Bug bounties

### Advanced Questions

#### How does Tendermint consensus work?

Tendermint BFT provides:

* Instant finality
* Byzantine fault tolerance
* No forks or reorgs
* High performance

[Learn more](/iopn/developer-docs/core-concepts/network-architecture.md)

#### What's the state management model?

Ethereum-compatible state:

* Account model
* Patricia Merkle tries
* Storage slots
* State root calculation

#### Can I run MEV bots?

MEV on OPN Chain:

* Different dynamics due to fast blocks
* No mempool sniping
* Fair ordering
* Reduced MEV opportunities

#### Is there a grants DAO?

Governance structure:

* Community DAO (planned)
* Validator governance
* Grant distribution
* Protocol upgrades

***

**Still have questions?**

* Ask in [Discord](https://discord.gg/iopn)&#x20;
* Contact <info@iopn.io>


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://iopn.gitbook.io/iopn/developer-docs/help/frequently-asked-questions.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.