Arbitrum One - Flagship Chain

Arbitrum One adalah chain Layer-2 unggulan dari ekosistem Arbitrum, berjalan di atas teknologi Nitro. Dioptimasi untuk DeFi, RWA (Real World Assets), NFT, dan aplikasi umum yang membutuhkan keamanan tinggi dengan throughput moderat.

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Overview Arbitrum One

$2.5B+

Total Value Locked

Largest L2 by TVL

1M+

Daily Transactions

Consistently highest volume

100%

EVM Compatible

Geth-based, no code changes

Institutional

Grade Security

BlackRock, Circle, Tether

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Technical Architecture (Nitro Stack)

Komponen Arsitektur

1️⃣ Sequencer

• Mengurutkan dan mengeksekusi transaksi
• Saat ini tersentralisasi (Offchain Labs)
• Rencana desentralisasi di roadmap

2️⃣ State Transition Function (STF)

• Lingkungan eksekusi berbasis WASM
• Menjalankan fork Geth
• Memproses transaksi dan compute state changes

3️⃣ RPC Nodes

• Full node yang menyinkronkan state chain
• Melayani permintaan baca (eth_call, eth_getBalance)
• Menyiarkan transaksi ke sequencer

4️⃣ Validators

• Monitor output sequencer
• Dapat menantang transisi state tidak valid
• Menggunakan fraud proofs untuk dispute

5️⃣ Bridge Contracts (L1)

• Inbox: Menerima transaksi dari L1
• Outbox: Menangani withdrawal ke L1
• Rollup Contract: Menyimpan state commitments

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How Transactions Work

Transaction Lifecycle:

Step 1: User Sends Transaction

User → MetaMask → RPC Node → Sequencer

• User signs transaction dengan private key
• Dikirim ke RPC node
• Forwarded ke sequencer

Step 2: Sequencer Processes

Sequencer → Include in batch → Execute in AVM

• Transaksi diurutkan (ordering)
• Dieksekusi di virtual machine
• State updated locally

Step 3: Soft Confirmation (~250ms)

Sequencer → User Receipt

• User menerima konfirmasi instant
• Transaksi muncul di wallet
• State visible di dApp

Step 4: Batch Posted to L1 (~10-15 minutes)

Batch → Compressed → Posted to Ethereum L1

• Multiple transactions digabung
• Data dikompresi
• Posted sebagai calldata ke L1

Step 5: Challenge Period (7 days)

Validators → Monitor → Challenge if invalid

• Validator check validity
• Jika invalid, submit fraud proof
• Jika valid, no action needed

Step 6: Finality

After 7 days → State final on Ethereum

• Setelah challenge period, state final
• Funds dapat ditarik ke L1 dengan keamanan penuh

Transaction Speed

• Soft confirmation: ~250ms (instant UX)
• L1 inclusion: ~10-15 minutes (on Ethereum)
• L1 finality: 7 days (after challenge period)

Untuk sebagian besar use cases, soft confirmation sudah cukup! 7 hari hanya diperlukan untuk withdrawal ke L1.

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Major Protocols on Arbitrum One

DeFi Powerhouses

Protocol	Category	TVL/Metrics	Why on Arbitrum
GMX	Perpetual DEX	$500M+ TVL	Low fees crucial untuk high-frequency trading
Uniswap V3	Spot DEX	$300M+ TVL	Largest DEX volume on any L2
Aave V3	Lending	$200M+ TVL	Cross-chain liquidity protocol
Radiant Capital	Omnichain Lending	$150M+ TVL	Arbitrum-native cross-chain money market
Camelot	DEX + Launchpad	$100M+ TVL	Arbitrum-native ecosystem hub
Curve Finance	Stable Swaps	$80M+ TVL	Efficient stablecoin trading

Gaming & NFTs

Protocol	Category	Key Feature
Treasure DAO	Gaming Ecosystem	Decentralized game publisher, 50K+ players
TofuNFT	NFT Marketplace	Multi-chain NFT marketplace
Battlefly	Strategy Game	NFT mechs, competitive gameplay

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Development Setup

Prerequisites

# Verify Node.js installation
node --version  # v18+
npm --version

# Install Hardhat globally (optional)
npm install -g hardhat

Hardhat Configuration

// hardhat.config.js
require("@nomiclabs/hardhat-ethers");
require("@nomiclabs/hardhat-etherscan");

module.exports = {
  solidity: {
    version: "0.8.20",
    settings: {
      optimizer: {
        enabled: true,
        runs: 200
      }
    }
  },
  networks: {
    // Arbitrum One Mainnet
    arbitrumOne: {
      url: "https://arb1.arbitrum.io/rpc",
      chainId: 42161,
      accounts: [process.env.PRIVATE_KEY]
    },
    // Arbitrum Sepolia Testnet
    arbitrumSepolia: {
      url: "https://sepolia-rollup.arbitrum.io/rpc",
      chainId: 421614,
      accounts: [process.env.PRIVATE_KEY]
    }
  },
  etherscan: {
    apiKey: {
      arbitrumOne: process.env.ARBISCAN_API_KEY,
      arbitrumSepolia: process.env.ARBISCAN_API_KEY
    }
  }
};

Deploy Script

// scripts/deploy.js
const hre = require("hardhat");

async function main() {
  console.log("Deploying to Arbitrum...");

  // Get contract factory
  const MyContract = await hre.ethers.getContractFactory("MyContract");

  // Deploy contract
  const contract = await MyContract.deploy();
  await contract.deployed();

  console.log("✅ Contract deployed!");
  console.log("Address:", contract.address);
  console.log("Network:", hre.network.name);
  console.log("Chain ID:", hre.network.config.chainId);
  console.log("Explorer:", `https://sepolia.arbiscan.io/address/${contract.address}`);
}

main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });

Deploy Commands

# Deploy ke Arbitrum Sepolia Testnet
npx hardhat run scripts/deploy.js --network arbitrumSepolia

# Deploy ke Arbitrum One Mainnet
npx hardhat run scripts/deploy.js --network arbitrumOne

# Verify contract on Arbiscan
npx hardhat verify --network arbitrumSepolia DEPLOYED_CONTRACT_ADDRESS

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Kasus Penggunaan Ideal untuk Arbitrum One

✅ Perfect Fit:

🏦 DeFi Trading

• DEX, perpetual, lending protocols
• Benefit dari low fees + high security

🖼️ NFT Marketplaces

• Minting dan trading NFT affordable
• Royalties enforcement on-chain

🏢 Real World Assets (RWA)

• Tokenisasi real estate, bonds, securities
• Memerlukan institutional-grade security

🏛️ DAO Governance

• On-chain voting hemat biaya
• Treasury management dengan gas rendah

🌾 DeFi Yield Farming

• Complex strategies viable
• Gas tidak menggerus profit

💵 Stablecoin Transfers

• USDC, USDT, DAI transfer murah
• Enable payment use cases

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Bridging Assets

Native Bridge (Official Arbitrum)

L1 → L2 (Deposit):

• ⏱️ Time: ~10-15 minutes
• 💰 Cost: Pay L1 gas fees (~$5-20)
• 🔒 Security: Fully trustless

L2 → L1 (Withdrawal):

• ⏱️ Time: 7 days (challenge period)
• 💰 Cost: Pay L2 gas to initiate, L1 gas to claim
• 🔒 Security: Fully trustless

Bridge URL: bridge.arbitrum.io

Third-Party Bridges (Fast, with trade-offs)

Bridge	Speed	Trust Model	Cost
Stargate	Instant	LayerZero relayers	~0.1%
Synapse	Instant	Liquidity pools	~0.1%
Hop Protocol	5-10 min	Optimistic bridge	Lower
Across	Instant	Intent-based	Competitive

Trade-off

Fast bridges memberikan instant transfers tapi memerlukan trust assumptions. Native bridge sepenuhnya trustless tapi membutuhkan 7 hari untuk L2 → L1.

Recommendation: Gunakan native bridge untuk large amounts, fast bridges untuk convenience.

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Gas Optimization Tips

Arbitrum-Specific Optimizations

// 1. Calldata Compression (automatic in Nitro)
// Repetitive calldata automatically compressed → cheaper L1 posting

// 2. Batch Operations
contract BatchMint {
    function batchMint(address[] calldata recipients) external {
        for (uint i = 0; i < recipients.length; i++) {
            _mint(recipients[i], tokenId++);
        }
    }
}
// Single batch tx jauh lebih murah dari multiple separate txs

// 3. Use Events Sparingly
// Events contribute to calldata size
emit TransferBatch(ids, amounts); // ✅ Better
// vs multiple:
emit Transfer(id1, amount1);      // ❌ More expensive
emit Transfer(id2, amount2);

// 4. Storage Patterns (sama seperti L1)
// SSTORE, SLOAD expensive
// Memory operations, calldata cheap

// 5. Utilize L2-Specific Precompiles
ArbSys arbSys = ArbSys(address(100));
uint256 l2BlockNumber = arbSys.arbBlockNumber();
bytes32 l2BlockHash = arbSys.arbBlockHash(blockNumber);

Example: Cost Comparison

// Simple ERC-20 Transfer
// Ethereum L1:  ~$10-20
// Arbitrum One: ~$0.50-1
// Savings: 10-20x

// Complex DEX Swap
// Ethereum L1:  ~$50-100
// Arbitrum One: ~$2-5
// Savings: 20-25x

// NFT Mint
// Ethereum L1:  ~$50-150
// Arbitrum One: ~$5-10
// Savings: 10-15x

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Important Considerations

⚠️ Trade-offs dan Keterbatasan:

7-Day Withdrawal

• Withdrawal native membutuhkan 7 hari untuk finality L1
• Gunakan fast bridges untuk instant exit (dengan trust assumptions)

Sequencer Tersentralisasi

• Saat ini sequencer tunggal (Offchain Labs)
• Roadmap: desentralisasi sequencer network
• Risk: Single point of failure (mitigated by forced inclusion)

MEV Considerations

• Sequencer dapat reorder transaksi dalam blok
• Similar dengan validator Ethereum
• Frontrunning masih mungkin

L1 Gas Dependency

• Biaya posting ke L1 berfluktuasi dengan Ethereum gas prices
• Ketika L1 congested, L2 fees naik juga (tapi tetap jauh lebih murah)

State Growth

• Full node perlu store seluruh history
• Pruning sedang dikembangkan untuk reduce storage

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Network Information

Arbitrum One Mainnet

Network Name:     Arbitrum One
RPC URL:          https://arb1.arbitrum.io/rpc
Chain ID:         42161
Currency Symbol:  ETH
Block Explorer:   https://arbiscan.io

Arbitrum Sepolia Testnet

Network Name:     Arbitrum Sepolia
RPC URL:          https://sepolia-rollup.arbitrum.io/rpc
Chain ID:         421614
Currency Symbol:  ETH
Block Explorer:   https://sepolia.arbiscan.io

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Resources

🔧 Developer Tools

• Arbiscan - Block explorer
• Arbitrum Bridge - Official bridge
• Portal - Ecosystem dApps
• Faucet - Testnet tokens

📊 Analytics

• DefiLlama - TVL analytics
• L2Beat - Metrics
• Dune Analytics - On-chain data

💰 Grants & Support

• Arbitrum Grants - Funding for builders
• Developer Discord - Get support

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Next Steps

Di modul berikutnya, kita akan explore Arbitrum Nova - chain gaming & social dengan biaya ultra-rendah menggunakan AnyTrust technology!

Ready to Build on Arbitrum One? 🚀

Deploy your first contract dan join ekosistem terbesar L2!