Circle's Arc public chain releases a post-quantum cryptography roadmap, covering full-stack upgrades from wallets to validators

According to the official blog, Circle's institutional-grade blockchain Arc has released a phased upgrade roadmap for post-quantum cryptography (PQ), planning to introduce post-quantum signature schemes at the launch of the mainnet, gradually covering full-stack layers such as private state protection, infrastructure hardening, and validator authentication.

The Arc mainnet will support post-quantum signatures from the outset, using an opt-in mechanism that does not require mandatory migration or a full network reset, allowing users to independently create wallets with long-term security. The recent goal is to extend quantum resistance to the private virtual machine (VM) layer, protecting private balances, private transactions, and private payees, with public keys additionally encapsulated in a symmetric encryption layer under privacy mode.

The mid-term plan is to advance the upgrade of the infrastructure layer, aligning with industry standards such as TLS 1.3, covering access control, cloud environments, and hardware security modules (HSM). The long-term goal is to complete the hardening of validator signatures. Given that Arc's block finalization time is less than 1 second, the current assessment considers the risk of quantum attacks in this phase to be relatively limited, and it will be steadily advanced after the post-quantum consensus toolchain matures.

Circle also warns that attackers may adopt a "collect now, decrypt later" strategy, and institutions should plan their cryptographic migration paths as early as possible.