Fhenix, a possible layer-2 community that wishes to convey totally homomorphic encryption (FHE) to good contracts, has revealed a technical white paper for the primary FHE rollup.
FHE itself is a type of encryption that ensures the confidentiality of the info even whereas it’s getting used, for instance in good contracts, as a result of knowledge can stay encrypted and processed with out ever needing to be decrypted.
This permits Ethereum and different EVM networks to course of info privately, with potential functions associated to non-public voting and confidential gaming — akin to poker, for instance.
Learn extra: Encryption startup Fhenix raises $7M for personal computation
Not like zero-knowledge (ZK) know-how, FHE is totally personal, Fhenix CEO Man Itzhaki advised Blockworks.
“With ZK, there may be an entity referred to as a prover that truly sees the knowledge,” Itzhaki explains, “so confidentiality arises from the truth that this prover is being positioned on the consumer facet, producing the ZK proofs.”
One limitation is that it precludes use circumstances requiring computation on knowledge that comes from a number of customers, he mentioned.
This isn’t the case for FHE-based methods, Itzahki mentioned. With FHE, knowledge and computation is finished on-chain, with out the necessity for a prover or one other entity.
“Our total imaginative and prescient at Fhenix is to create an FHE stack that can permit builders to construct functions with knowledge confidentiality, and for customers to learn out of those functions by growing their stage of safety and privateness,” he mentioned.
FHE in and of itself goes past simply safeguarding privateness, Man Zyskind, the founding father of SCRT Labs (the staff behind the Secret Community) advised Blockworks.
“This isn’t nearly defending folks’s privateness — lack of on-chain encryption is the explanation why we’re very restricted within the functions we will construct on blockchains at this time. As an illustration, think about creating an on-chain poker sport. With out encryption, gamers’ fingers could be seen to all, rendering the sport unplayable,” he mentioned.
Zyskind notes that current privacy-focused blockchains rely closely on zero-knowledge proofs, which fall quick in terms of the mixing of personal knowledge from a number of sources, akin to in an on-chain poker sport or a sealed-bid public sale contract.
“Zero-knowledge proofs are extra suited to single-user situations, akin to verifying age with out revealing the precise beginning date. In these circumstances, zk proofs are efficient however inadequate for complicated, multi-party personal knowledge integration, the place FHE rollups develop into important,” he mentioned.
Utilizing an optimistic rollup construction
The FHE rollup white paper outlines the usage of an optimistic rollup construction, a call, Itzahki notes, which can allow the rollup to be each scalable and personal.
Though utilizing a zk rollup structure shouldn’t be fully out of the query, Itzahki explains that it will be troublesome to create a rollup resolution that mixes two very heavy-duty cryptographic methods.
“At this time second, the implementation of FHE by optimistic [rollup structures] is far more environment friendly,” he mentioned.
One of many key breakthroughs for Fhenix was devising an efficient mechanism for fraud proofs when utilizing an optimistic rollup.
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Itzahki explains that the staff was in a position to introduce a fraud-proof mechanism utilizing internet meeting, a low-level computing language, which can allow fraud verification to be enacted in the identical manner as if the info was not encrypted.
“Moderately than [running] on the native EVM itself, that mechanism allows us to examine if that internet meeting code as change, and lets us know if there’s a fraudulent transaction,” he mentioned.
Modular design
The FHE rollup can be designed modularly, that means that it’ll draw from totally different elements to create the blockchain.
“Now we have a separation between the sequencer, validator, and the info availability layer,” Itzahki mentioned. “The information availability layer is usually Ethereum, then we at Fhenix will deal with the sequencer and handle the execution, the validator, and the prover.”
Having a modular design will allow cryptographic improvements akin to FHE to execute extra effectively, enabling it to give attention to its strengths the place wanted.
“We don’t essentially must have [FHE] all through the whole elements. In order that’s why we’re going with a modular design,” Itzahki provides.
Kyle Samani, managing companion at Multicoin Capital, an investor in Fhenix, mentioned the protocol’s rollup is a first-of-its-kind layer-2 that can convey FHE on-chain in a usable manner.
“The white paper is a essential first step in serving to builders notice that L2’s can be utilized for extra than simply scaling. They will now be used to increase the performance of functions into new design areas,” Samani mentioned.
Fhenix plans to launch the testnet of its first FHE rollup within the first quarter of 2024. It’s undecided whether or not the rollup stack can be constructed open-source, although testing can be obtainable to any tasks.
