Move over, legacy crypto. Circle’s Arc Layer 1 blockchain, designed for stablecoin financing and institutional use, will debut with quantum resistance features designed to survive a future in which traditional blockchains could collapse under quantum attacks.
“On mainnet, Arc will introduce a post-quantum signature system, providing users with a practical design path to create quantum-resistant wallets,” Arc said in an update on Thursday. The update did not mention the timetable for the mainnet launch.
This means that Arc benefits from quantum resistance from day one, unlike existing chains, which may wait to add this feature later as a patch. So when users create a wallet on mainnet, they can choose a signature method that future quantum computers will not be able to break. This will ensure the long-term security and protection of crypto assets in wallets.
Every blockchain wallet relies on a super-secure digital signature or key to prove you own your tokens and authorize transactions. When you press “send” on your crypto, your wallet signs the transaction with this code and the network verifies it before moving the coins. Today’s computers are not powerful enough to operate this process, access your key and dump your coins.
However, a future quantum computer could do this in at least two ways: a long attack and a short attack, as CoinDesk explained on Sunday.
In short, what seems unbreakable today may not be tomorrow, and that’s why Arc is proposing a quantum-resistant signature method from the start.
Arc’s announcement comes as Google’s report on quantum threats to the Bitcoin and Ethereum blockchains raises new questions about the long-term reliability of digital ledgers. However, developers have been tackling the problem for months and coming up with early solutions. At the same time, startups like Postquant Labs are exploring how quantum hardware could actually strengthen blockchain networks.
Arc’s choice to build a quantum resistor from scratch could make it particularly attractive to institutions. The blockchain launched its testnet in October, using Circle’s dollar-pegged stablecoin USDC as its native currency for gas fees. USDC, with a market cap of around $77.5 billion, is only lagging behind in size and stands out as a regulated stablecoin favored by institutions.
Arc’s roadmap also includes ensuring that sensitive financial information remains private in the quantum age. Its near-term plan focuses on protecting private balances, confidential payments and recipient information with quantum-resistant cryptography, not just quantum-resistant wallet keys. This way, the confidential financial activity of institutions using Arc will remain private.
The mid-term phase will focus on closing backdoors through which a quantum attack could occur. These backdoors are the cloud servers on which validators run, the hardware security modules that store keys, and the encrypted connections between nodes. That’s like fortifying an entire building, not just the safe in your bedroom closet.
In the long term, Arc will focus on the validator layer. Validators are the computers – run by trusted institutions – that confirm transactions and add new blocks to the distributed ledger.
Arc’s current design finalizes a block in less than a second, according to the official blog. This leaves the future quantum attacker with an extremely short window of time to derive a user’s private key and forge a signature. The risk is therefore low, but Arc is not unaware of it.
“Arc’s roadmap should target strengthening the validator signature after rigorous performance testing and implementing the necessary tools. Validator upgrades should occur when ready to preserve both network resilience and performance,” he said.
