Researchers propose a solution that does not require soft fork and instead enables private transfers in the form of Zcash to Bitcoin

Three researchers from the cryptography research institute Alloc Init published a paper on Thursday proposing a system called Shielded Bitcoin that attempts to introduce an Zcash -style privacy transfer function for Bitcoin without modifying the underlying protocols of Bitcoin . The scheme does not require soft fork and thus avoids the community threshold most difficult to overcome by changing the consensus in Bitcoin ;

Encrypted notes plus zero-knowledge proof , Bitcoin only when coins are released with the sorting layer

Shielded Bitcoin was co-written by Clara Shikhelman, Mikhail Komarov and Aleksei Moskvin. The core idea of the program is to hide transaction amounts, senders, receivers and links with previously spent funds using encrypted notes and zero-knowledge proof .

Contrary to conventional assumptions, this set of privacy protocols is not enforced by crypto miner . Researchers have positioned Bitcoin as a neutral publishing and sorting layer with an independent software called the indexer responsible for verifying zero-knowledge proof , checking whether funds are duplicated, and reconstructing the state of the shielding system.

By design, Shielded Bitcoin explicitly borrows from the architecture of Zcash : it also uses a public nullifier for encrypting notes, marking notes that have been spent, and proving transactions valid. The difference is that Shielded Bitcoin does not run its own blockchain and consensus mechanism , but rather parasites on top of Bitcoin .

Question and disagreement: Anonymous collections, quantum security in focus

Following the announcement, developer Vadim Zavodil criticized X. He argued that much of the privacy technology in Zcash had been implemented and questioned whether a new system's initial privacy capabilities lacked an anonymity set built up over many years by a newly created shield pool.

The Shielded Bitcoin researcher acknowledges this limitation in an accompanying note: large deposits do not automatically form a large anonymous pool. Observers may still narrow the scope of associations between transfers if a small number of participants created most of the notes, or certain wallet behavior characteristics are apparent.

Another question comes from the quantum security level. Pierre-Luc Dallaire-Demers, founder of post-quantum cryptography company Pauli Group evaluates the architecture as interesting but argues that it does not have any anti-quantization properties at all. He then says he is exploring what a fully post- Quantum version should look like assuming Bitcoin adopts future post-Quantum signature schemes.

In contrast, Zerocash co-author and StarkWare CEO Eli Ben-Sasson was more supportive of the direction. He responded by saying that Zerocash's paper (the predecessor to Zcash ) was originally intended to bring privacy into Bitcoin . However, he also said that he hadn't read through Shielded's Bitcoin paper yet, only wishing to see a vision for achieving privacy and scalability via zero-knowledge proof settle at the Bitcoin base layer.

Follow-up: Balance between privacy and compliance still to be tested

In context, Bitcoin itself only provides pseudonyms rather than real privacy and the on-chain analytics tool has made it easier to track money flows. Previous attempts at privacy - whether a Tornado Cash-type hybrid or various sidechain schemes - have faced regulatory pressures or high user migration costs. The route of shielded Bitcoin does not require changes in protocols, which theoretically leaves users with lower technological thresholds for adoption, but also means that privacy effects are entirely dependent on participant size.

Furthermore, Zcash has previously announced that its November upgrade could freeze funds left in the Sprout pool and the evolution of the privacy coin ecosystem itself is occurring simultaneously. For ordinary token holders, this proposal will not change how Bitcoin is used anytime soon, but it reflects a trend towards zero-knowledge proof moving from an independent public blockchain to the ecological threshold of Bitcoin .