Why Is the Transaction Data Hashed before Being Included in the Tree?

The transaction data is hashed first to standardize the input size. Cryptographic hash functions produce a fixed-size output (e.g.

32 bytes for SHA-256) regardless of the input size. This uniformity is essential for the tree construction, where hashes are concatenated and re-hashed.

It also provides the initial integrity check for the individual transaction data.

What Is a ‘Merkle Tree’ and How Does It Use Cryptographic Hashing?
Can a Financial Derivative Contract Be “Hashed” for Off-Chain Proof?
What Role Does Hashing Play in Creating an ECDSA Signature?
How Does Hashing Compare to Traditional Methods like Notarization for Contract Integrity?
How Is the Merkle Tree Related to Hashing?
Why Is It Dangerous to Sign the Raw Transaction Data Instead of Its Hash?
What Are the Regulatory Requirements for Data Integrity in Derivatives Clearing, and How Does Hashing Help Meet Them?
What Is the Difference between ‘Last Look’ and ‘Pre-Trade Credit Check’ in Derivatives Trading?

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