How OP_NET Extends Bitcoin

No Protocol Modifications Required

OP_NET extends Bitcoin's capabilities without changing Bitcoin at all. It's not a soft fork or hard fork. It's an optional consensus layer that exists on top of Bitcoin, available to anyone who wants it, invisible to anyone who doesn't.

If you don't run OP_NET, you just see normal Bitcoin transactions with some extra witness data. If you do run OP_NET, you see a complete smart contract platform with deterministic execution and cryptographic consensus.

Data Embedded in Bitcoin

Every OP_NET transaction is a standard Bitcoin transaction. The difference lies in what's embedded in the tapscript witness data:

• Contract Deployments: Compressed WebAssembly bytecode (up to 400KB using ZLIB compression).
• Contract Calls: Function selectors, parameters, and ML-DSA signatures.
• Epoch Solutions: SHA-1 near-collision proofs and state attestations.

Bitcoin miners include these transactions because they pay fees like any other transaction. Bitcoin doesn't need to understand what the data means. It just provides data availability and timestamping.

Consensus Layer Architecture

A consensus layer can have its own block positioning algorithms, transaction ordering, or finality rules that work completely independent of how Bitcoin miners order things. Bitcoin just provides:

• Data Availability: OP_NET data is embedded in Bitcoin transactions and available forever.
• Timestamping: Bitcoin blocks provide a global ordering of events.
• Immutability: Once data is in Bitcoin, it cannot be changed without reorging Bitcoin.

OP_NET interprets and orders that data according to its own rules. Transactions are sorted by gas price, priority fees, then transaction ID. This ordering is independent of how Bitcoin miners included them.

What OP_NET Adds to Bitcoin

Turing-Complete Smart Contracts

Bitcoin Script is intentionally limited. No loops, no state, ~520 byte limit. OP_NET adds:

• Full WebAssembly execution (loops, recursion, complex logic).
• Persistent state storage (balances, contract variables).
• Up to 400KB compressed contract bytecode.
• Gas metering for computational costs.

Deterministic Execution

Every OP_NET node processes the same transactions and arrives at the exact same state. This is enforced through:

• Canonical transaction ordering within blocks.
• Deterministic WebAssembly execution.
• Epoch checkpointing with SHA-1 proof-of-work.
• Time-delayed attestations to immutable history.

Post-Quantum Security

OP_NET requires ML-DSA (Module-Lattice Digital Signature Algorithm) for contract interactions. This NIST-standardized post-quantum signature scheme protects against both classical and quantum computer attacks.

Token Standards

OP_NET provides standardized token interfaces:

• OP-20: Fungible tokens (like ERC-20 on Ethereum).
• OP-721: Non-fungible tokens (like ERC-721 on Ethereum).

Contract Addresses (P2OP)

OP_NET introduces P2OP addresses using SegWit version 16 with custom HRP. These addresses represent deployed smart contracts and are distinct from standard Bitcoin addresses.

What Bitcoin Provides

Bitcoin's existing properties that OP_NET leverages:

• Decentralization: Over 15,000 reachable nodes worldwide.
• Security: Highest hash rate and most secure network in crypto.
• Liquidity: Deepest liquidity and widest adoption.
• Stability: 14+ years of proven reliability, conservative upgrades.
• Censorship Resistance: Miners include OP_NET transactions because they pay fees.

Comparison: Bitcoin vs Bitcoin + OP_NET