Ledger LandISSUE #19 of 90

transactions · inputs · outputs · fees

BlockyVSDouble-Spend Dan

Blocky saysA transaction moves value or triggers a contract, paying a fee for inclusion.

A transaction specifies sender, recipient, amount/data, a nonce (ordering/replay protection), and a fee that pays the block producer. It must be signed by the sender's private key. Bitcoin models value as unspent outputs (UTXOs); Ethereum uses account balances. Either way, fees ration limited block space — pay more to be included sooner.

Power-ups you unlock

Sender, recipient, amount/data, nonce, fee
Must be signed by the sender
Fee pays for limited block space
UTXO (Bitcoin) vs account (Ethereum) models

Double-Spend Dan attacks — common mistakes

Reusing a nonce or getting nonce order wrong
Setting a fee too low to ever be included
Confusing UTXO and account accounting

Boss battleList the fields a transaction needs and why the nonce matters.

Example code

<!doctype html><html><head><meta charset="utf-8"></head>
<body style="background:#06040d;color:#e6e0ff;font-family:monospace;padding:20px"><pre>{ from, to, value, nonce, fee, signature }
nonce: ordering + replay protection
fee: bids for limited block space</pre></body></html>

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