Introduction to PoEM

Quai Network’s Proof-of-Entropy-Minima consensus mechanism.

The Consensus Problem

Traditional blockchains face a fundamental challenge: when two valid blocks are found simultaneously, the network temporarily splits. This creates:

• Uncertainty: Transactions may be reversed if you’re on the losing fork

• Wasted energy: Miners work on competing chains that will be discarded

• Limited scalability: Only one chain can win, limiting overall throughput

Quai Network solves this with Proof-of-Entropy-Minima (PoEM), ensuring the network never splits and always stays unified.

​How PoEM Works

PoEM is inspired by Bitcoin’s Proof-of-Work (PoW) Nakamoto Consensus, but with a crucial improvement. Like PoW, PoEM uses hashes generated by competing miners to verify proposed blocks. However, PoEM differs in how these hashes are compared and measured.Think of entropy like a “uniqueness score” - PoEM always picks the block with the highest uniqueness score, ensuring every node makes the same choice.Unlike PoW, which treats all blocks that meet a certain difficulty level as equally valid, PoEM measures the intrinsic block weight to calculate the entropy, or randomness, removed by each proposed block. This ensures that all nodes will always prefer one particular block over any other options.Under PoEM, all nodes immediately agree on the next block as soon as they become aware of it, eliminating any disagreements caused by delays in the network. Two nodes running PoEM will always agree on which block is next in the chain.

​PoEM vs Traditional Consensus

Traditional PoW	PoEM
”Good enough” blocks compete	Best block always wins
Network splits temporarily	Network stays unified
Resolution takes time	Resolution is instant
Wasted mining effort	All mining contributes
Limited to single chain	Enables infinite shards

​Key Benefits

By removing contention from consensus, PoEM enables “perpetual consensus” - the network never needs time to resolve conflicts because conflicts never occur. This breakthrough provides several advantages:For Users:

• Instant finality: Transactions are immediately final, no waiting for confirmations

• Predictable fees: No congestion from competing chains

• Unlimited capacity: Network can scale infinitely without degrading security

For the Network:

• Energy efficiency: No wasted mining on discarded forks

• True decentralization: Can coordinate unlimited execution shards

• Enhanced security: All mining power secures the entire network