Ledger LandISSUE #12 of 90

proof of authority · permissioned chains

BlockyVSDouble-Spend Dan

Blocky saysProof of Authority trusts a known set of approved validators — fast, but not decentralized.

PoA names a fixed set of trusted validators (by identity/reputation) who take turns producing blocks. It's fast, cheap, and high-throughput — great for private/consortium chains and testnets — but it sacrifices decentralization: you must trust the authorities. Use it when participants are known and accountable, not for a permissionless public network.

Power-ups you unlock

Approved, identified validators produce blocks
Fast, cheap, high throughput
Sacrifices decentralization (trust the authorities)
For private/consortium chains and testnets

Double-Spend Dan attacks — common mistakes

Using PoA where trustlessness is required
Assuming PoA chains are censorship-resistant
Confusing private-chain speed with public security

Boss battlePick PoW, PoS, or PoA for an internal company supply-chain ledger.

Example code

<!doctype html><html><head><meta charset="utf-8"></head>
<body style="background:#06040d;color:#e6e0ff;font-family:monospace;padding:20px"><pre>internal/known parties → PoA (fast, trusted set)
public/permissionless  → PoW or PoS (trustless)</pre></body></html>

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