A spark evoluiu essa ideia da statechain, melhorando alguns aspectos. No artigo acima diz o grosso da idéia da statechain: Statechains are a layer two protocol, meaning it enables the transfer of value without burdening the Bitcoin blockchain. This can help with scaling and save fees. Unlike Lightning it is not trustless, but it maintains a high degree of censorship resistance (more so than federated sidechains) due to the fact that withdrawing on-chain is permissionless. The basic idea behind Statechains is that you lock up money between two parties in a 2-of-2 multisig: the Statechain entity and the user. When the user wants to transfer the money (the entire UTXO), they simply hand over their private key, which we call the transitory key, to the intended recipient.