TL;DR
Tezos has launched TzEL, a post-quantum privacy system for blockchain payments on testnet. Co-founder Arthur Breitman criticized parts of the Bitcoin community for downplaying legitimate quantum risks to blockchain privacy.
In brief
- Tezos launched TzEL, a post-quantum privacy system for blockchain payments on testnet.
- Arthur Breitman accused parts of the Bitcoin community of dismissing legitimate quantum risks.
- The project aims to protect encrypted blockchain transaction data from future decryption attacks.
While practical quantum computers capable of breaking modern cryptography do not yet exist, Tezos co-founder Arthur Breitman said some pockets of the crypto industry are treating quantum computing like a conspiracy theory while ignoring a legitimate threat to blockchain privacy.
The warning comes as Tezos launches TzEL, a post-quantum privacy system on testnet designed to protect private payments and encrypted transaction data from future “harvest now, decrypt later” attacks. Breitman said Tezos is acting with “a sense of urgency,” while parts of the industry remain complacent about quantum threats in his view.
“Some projects are barely maintained and won’t be upgraded at all; but the important ones will be upgraded, mostly in a timely fashion,” Breitman told Decrypt.
Breitman took particular issue with some in the Bitcoin community promoting what he described as pseudo-scientific theories about quantum computing.
“There are Bitcoiners being applauded on stages for half-baked crank theories about quantum mechanics that fly in the face of established physics,” he said.
The cultural debate centers on whether blockchain networks should begin preparing now for a future where quantum computers could break the elliptic curve cryptography widely used across crypto today.
The concern is especially acute because blockchain data is permanent. By design, transactions and other data are stored publicly on-chain indefinitely, creating the potential for what security researchers call a “harvest now, decrypt later” attack.
In such a scenario, attackers collect blockchain data in the form of public keys and store them until quantum computers become powerful enough to break the cryptography protecting them, thus exposing private keys and allowing for funds to be stolen.
One challenge facing post-quantum privacy systems, however, is scale. Quantum-resistant zk-STARK proofs are substantially larger than the proofs used in many existing blockchain privacy tools, creating storage and throughput problems. Breitman said that Tezos is equipped to handle that challenge.
“Post-quantum shielded transactions can take up a lot of space,” he said. “Tezos has a functioning data availability layer that can absorb them without increasing the load for consensus nodes.”