Stellar developers unveiled a three-step roadmap to shift its cryptographic system to counter threats from quantum computers. The plan is to begin converting corporate wallets from 2026 and allow all accounts to upgrade to a quantum-resistant cryptographic system by the end of 2027 while keeping their existing addresses.

Blockchain media outlet Decrypt reported on June 9 that the Stellar Development Foundation (SDF) announced a long-term security strategy to prepare for advances in quantum computing and unveiled a phased transition plan.

At the core of the roadmap is that the Stellar network uses a structure that separates account addresses from signing keys. The foundation explained that this design allows users to switch to a quantum-resistant signature system without creating new addresses or moving assets to another account. Stellar said this makes the upgrade burden relatively smaller than for bitcoin or ethereum, where an address is closely linked to a public key.

Stellar outlined two broad quantum computing threats. One is an attacker forging a validator's signature and disrupting the network's consensus process. The other is deriving a private key from a public key and seizing a user's account.

The Stellar Development Foundation said the risk of account takeover is the more realistic and complex problem, and that the roadmap focuses on reducing that risk.

The transition plan will proceed in 3 phases. In the first phase, in 2026, Stellar will add quantum-resistant signature verification to its smart contract platform. It plans to support corporate wallets and institutional users so they can adopt the new security system first.

In the second phase, in 2027, Stellar plans a protocol upgrade so all Stellar accounts can add quantum-resistant signers while keeping their existing addresses.

The final phase is to fully retire the cryptographic system currently in use. The foundation said it will decide the specific timing later, taking into account the pace of quantum computing development and the community's state of readiness.

There are challenges remaining. In particular, dormant accounts with no transactions over a long period are seen as the biggest variable in the transition process. If account holders cannot be contacted, a forced transition or a deadline could effectively result in accounts being frozen.

The Stellar Development Foundation said the issue cannot be resolved by technical judgment alone and should be decided through open, community-level discussion in the future.

The industry believes that if quantum computers advance sufficiently, they could neutralise elliptic curve cryptography, or ECC, used by most blockchain networks today. ECC is a core security technology for major blockchains including bitcoin, ethereum and Stellar. Concerns are also being raised that because blockchain transaction records and public key information are permanently 공개, data collected now could be decrypted all at once after the emergence of powerful quantum computers in the future.

The expected timing of quantum threats is also being brought forward. The U.S. National Institute of Standards and Technology (NIST) recently revised its estimate of when quantum security risks could materialise to 2029, from after 2030. Google is also said to have internally set 2029 as its target date for transitioning to quantum-resistant cryptography. The cryptocurrency industry is also speeding up efforts to prepare countermeasures, assuming around 2030 as "Q-Day".

Bitcoin and Ethereum are also reviewing quantum response strategies. Bitcoin developers are discussing various mitigation measures, and Ethereum developers are also operating a separate quantum response research team and seeking transition paths.

The industry is assessing Stellar's announcement as a case of joining in earnest the broader blockchain industry's move to prepare for a post-quantum era.

Meanwhile, the Stellar network's token XLM fell about 12 percent over the past week and traded around $0.196. Over the past 30 days, it was up about 15 percent.