Key Takeaways
Alloc Init researchers proposed Shielded Bitcoin, a design enabling Zcash-style private transfers on the Bitcoin base layer without soft forks.
According to BlockchainReporter, researchers at Bitcoin cryptography firm Alloc Init published a 56-page paper proposing Shielded Bitcoin, a design for Zcash-style private transfers on the Bitcoin base layer that requires no soft fork or consensus change. Authored by Clara Shikhelman, Mikhail Komarov, and Aleksei Moskvin, the specification hides the sender, recipient, and amount of a payment while Bitcoin records and orders the data without validation.
The design holds value in encrypted notes, using zero-knowledge proofs and nullifiers to prevent double spends. Separate software called indexers verifies the proofs and rebuilds the shielded state, treating Bitcoin as a neutral publication and ordering layer. The current paper covers only internal transfers, leaving deposits and withdrawals to a separate paper built on Bitcoin PIPEs v2.
The proposal utilizes the Groth16 proof system and publishes each transfer in an OP_RETURN output of roughly 625 vbytes, with estimated private transfer sizes around 700 vbytes. The paper arrives amid a broader privacy-coin revival, drawing mixed reactions from developers and researchers including Vadim Zavodil and Eli Ben-Sasson.
Source & Fact-Check Note
https://blockchainreporter.net/shielded-bitcoin-zcash-style-private-transfers/
