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Verifiable Randomness

🧱 Modular Blockchain: Unbundle the Stack

Learn how Celestia separates consensus, execution, and data availability

What is Modular Blockchain?

**Modular blockchain** is an architectural paradigm that separates core blockchain functions—consensus, data availability, execution, and settlement—into independent, specialized layers. Instead of forcing every node to do everything (monolithic), each layer focuses on one task and does it exceptionally well.

This separation of concerns enables **unprecedented scalability**: execution layers (rollups) can process 100,000+ TPS while inheriting security from consensus layers like Ethereum or Celestia. The result is a flexible, composable blockchain stack.

🏗️ Four Core Blockchain Functions

1
Consensus
Agreeing on transaction order and finality (PoS, PoW, BFT)
2
Data Availability
Ensuring transaction data is published and retrievable
3
Execution
Processing transactions and updating state (EVM, SVM, WASM)
4
Settlement
Verifying proofs and resolving disputes (fraud/validity proofs)

Interactive: Monolithic vs Modular Comparison

Compare the two fundamental blockchain architecture paradigms.

Monolithic Blockchain

All functions (consensus, execution, data availability, settlement) in one layer

Throughput
15-7,000 TPS
Cost per Tx
High (all nodes verify)
Flexibility
Low
Examples
BitcoinEthereum L1Solana
✓ Advantages
  • Simple design
  • Tight integration
  • Atomic composability
✗ Disadvantages
  • Limited scalability
  • Resource constraints
  • Upgrade complexity

The Scalability Trilemma

Traditional blockchains face an impossible tradeoff: optimize for **decentralization**, **security**, and **scalability**—pick two. Modular architecture breaks this trilemma by separating concerns.

🌐 Decentralization

Many independent nodes validate and participate

🛡️ Security

Resistant to attacks, censorship, and manipulation

⚡ Scalability

High throughput and low transaction costs

🚀 Why Modular Matters

📈
Unlimited scalability: Execution layers can scale horizontally without bottlenecks
🔧
Specialized optimization: Each layer uses best-in-class tech (WASM execution, DA sampling)
🎯
Sovereignty: Rollups choose their own execution environment, governance, and upgrades
💰
Cost efficiency: Shared DA layer amortizes costs across many rollups