Fhenix, a possible layer-2 community that desires to deliver absolutely homomorphic encryption (FHE) to sensible 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 sensible contracts, as a result of information can stay encrypted and processed with out ever needing to be decrypted.
This permits Ethereum and different EVM networks to course of data privately, with potential purposes associated to non-public voting and confidential gaming — akin to poker, for instance.
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In contrast to zero-knowledge (ZK) expertise, FHE is totally non-public, Fhenix CEO Man Itzhaki advised Blockworks.
“With ZK, there may be an entity known as a prover that really sees the data,” 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 instances requiring computation on information that comes from a number of customers, he mentioned.
This isn’t the case for FHE-based techniques, Itzahki mentioned. With FHE, information and computation is completed on-chain, with out the necessity for a prover or one other entity.
“Our general imaginative and prescient at Fhenix is to create an FHE stack that can permit builders to construct purposes with information confidentiality, and for customers to profit out of those purposes 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 workforce behind the Secret Community) advised Blockworks.
“This isn’t nearly defending individuals’s privateness — lack of on-chain encryption is the rationale why we’re very restricted within the purposes we are able to construct on blockchains right now. As an illustration, contemplate creating an on-chain poker recreation. With out encryption, gamers’ arms can be seen to all, rendering the sport unplayable,” he mentioned.
Zyskind notes that present privacy-focused blockchains rely closely on zero-knowledge proofs, which fall brief with regards to the combination of personal information from a number of sources, akin to in an on-chain poker recreation or a sealed-bid public sale contract.
“Zero-knowledge proofs are extra suited to single-user eventualities, akin to verifying age with out revealing the precise start date. In these instances, zk proofs are efficient however inadequate for complicated, multi-party non-public information 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 just isn’t fully out of the query, Itzahki explains that it will be tough to create a rollup resolution that mixes two very heavy-duty cryptographic techniques.
“At the moment second, the implementation of FHE by means of optimistic [rollup structures] is way 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 workforce was capable of introduce a fraud-proof mechanism utilizing internet meeting, a low-level computing language, which can allow fraud verification to be enacted in the identical method as if the info was not encrypted.
“Reasonably than [running] on the native EVM itself, that mechanism allows us to verify if that internet meeting code as change, and lets us know if there’s a fraudulent transaction,” he mentioned.
Modular design
The FHE rollup shall be designed modularly, which means that it’ll draw from totally different parts to create the blockchain.
“We now 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 deal with its strengths the place wanted.
“We don’t essentially have to have [FHE] all through your entire parts. In order that’s why we’re going with a modular design,” Itzahki provides.
Kyle Samani, managing accomplice at Multicoin Capital, an investor in Fhenix, mentioned the protocol’s rollup is a first-of-its-kind layer-2 that can deliver FHE on-chain in a usable method.
“The white paper is a important 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 purposes 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 shall be constructed open-source, although testing shall be out there to any tasks.