Stellar Advances Quantum Plans With Bell Upgrade: Potential Scenarios for XLM Price

In a recent X post, Stellar said the Bell (Protocol) upgrade aims to prepare smart accounts for businesses at scale and start work on quantum-safe signatures and faster ledgers. The upgrade is expected to happen next month, with testnet and mainnet upgrade dates likely to be Nov. 3 and 23, 2026.

Besides last week’s Stellar Core v30.0.0 stable release, there are more stable releases coming this week, including infrastructure and SDKs. As stated above, November 3 and 23, 2026 at 1700 UTC have been scheduled for testnet and mainnet upgrade votes.

Protocol 30 changes the ledger header format (CAP-88), and an older SDK may fail to decode Protocol 30 ledgers. The Protocol 30 SDKs carry the updated XDR definitions, plus support for the new muxed contract address type and its W strkey (CAP-84).

Stellar advances quantum-safe plans

In June 2026, Stellar introduced the Quantum Preparedness Plan (QPP) aiming to migrate the network to quantum-safe cryptography.

By the end of 2027, every Stellar account is expected to be able to add a quantum-safe signer through a native protocol upgrade, keeping the same address and history. Enterprise wallets are expected to be able to move to quantum-safe signing in 2026 through Soroban contract accounts.

XLM price to benefit

At the time of writing, XLM was up 4.80% in the last 24 hours to $0.183 as the broader crypto market rebounded. XLM’s price is set to benefit in the long run from Stellar’s Quantum Preparedness Plan, which improves the security of the network, especially that of accounts.

There are two threats to Stellar from sufficiently powerful quantum computers, and they require different solutions. First is network integrity: Stellar Consensus Protocol messages are authenticated with Ed25519 signatures by validators. An attacker who can forge enough validator signatures to control quorum intersection can compromise consensus itself. Network integrity will be addressed through a protocol upgrade to SCP.

Account takeover is the harder problem and the focus of the Quantum Preparedness Plan (QPP). Shor’s algorithm can derive the private key for any Ed25519 public key. On Stellar, account addresses directly encode the Ed25519 public key, which means every account address on the network is a target—including dormant accounts that have never authorized a transaction.