PaytoWitnessScriptHash

PaytoWitnessScriptHash, often abbreviated as P2WSH, is a type of Bitcoin script that provides enhanced security and efficiency for on-chain transactions. It is part of the Segregated Witness (SegWit) upgrade, a soft fork that was activated on the Bitcoin network in 2017.

P2WSH transactions allow users to spend Bitcoin by providing a cryptographic hash of the unlocking script rather than the script itself. This means that only the hash of the script is committed to the transaction's input. The actual unlocking script, along with the witness data, is moved to a separate part of the transaction called the witness data. This separation is what gives SegWit its name.

The primary benefits of P2WSH include reduced transaction sizes. By committing only the hash, the data required for the transaction input is smaller, leading to lower transaction fees for users. This also has the effect of increasing the overall transaction throughput of the Bitcoin network.

Furthermore, P2WSH contributes to improved security. Since the unlocking script is not directly included in the transaction input, it is less susceptible to signature malleability, a vulnerability that had previously plagued Bitcoin transactions. This makes P2WSH a more robust and secure way to handle Bitcoin spending.

To spend funds locked in a P2WSH address, a user must provide the original script and the correct witness data that satisfies the conditions defined by the script hash. This ensures that only authorized parties can access and spend the Bitcoin.