Transactions & Fees

Transaction Model

NOUS uses a UTXO model (Unspent Transaction Output), similar to Bitcoin:

• Each transaction consumes one or more inputs (previous unspent outputs)
• Each transaction creates one or more outputs
• The difference between inputs and outputs is the fee

Transaction Structure

Transaction {
  Version:  1
  ChainID:  mainnet
  Inputs:   [previous outputs being spent]
  Outputs:  [new outputs being created]
}

Each input includes a signature proving ownership. Each output locks funds to a public key hash.

Fees

• Fees = total input value - total output value
• The block producer collects all fees
• There is no protocol-enforced minimum fee
• A dust limit of 546 base units applies to regular outputs
• OP_RETURN outputs (data-only, unspendable) are exempt from the dust limit

OP_RETURN Messages

Transactions can include an OP_RETURN output to store arbitrary data on-chain:

• Maximum size determined by transaction size limits
• Value must be 0 (unspendable)
• Used for on-chain messaging and data anchoring

Confirmation

• Regular transactions: spendable after 1 confirmation
• Coinbase (mining reward): spendable after 100 confirmations (~4 hours)

Scripts

NOUS uses Pay-to-Public-Key-Hash (P2PKH) scripts:

• Lock script: OP_DUP OP_HASH160 <pubkey_hash> OP_EQUALVERIFY OP_CHECKSIG
• Unlock script: <signature> <pubkey>