Stellar has activated its Protocol 30 upgrade, codenamed Bell, on testnet, introducing new smart contract capabilities, post-quantum signature verification and changes that could allow faster ledger processing in future upgrades.
Summary
- Stellar has activated its Protocol 30 Bell upgrade on testnet, with validators scheduled to vote on mainnet activation on November 23 at 17:00 UTC.
- Bell introduces muxed contract addresses that allow exchanges, custodians and payment providers to manage multiple customer balances through a single smart contract.
- The upgrade adds support for post quantum ML DSA signature verification within smart contracts, while network transaction signatures will continue using Ed25519.
- Protocol 30 introduces millisecond ledger timing to support faster processing in future upgrades, although the change does not immediately reduce ledger closing times.
- Wallet providers, exchanges and infrastructure operators must update their software to support the new address format and ledger data changes before mainnet activation.
According to a November 4 announcement from the Stellar Development Foundation, the testnet upgrade has been completed, with validators now scheduled to vote on activating Bell on the mainnet on November 23.
The upgrade introduces three changes under CAP-84, CAP-87 and CAP-88, covering how smart contracts handle customer addresses, verify cryptographic signatures and record ledger closing times.
In its October 20 announcement, the foundation explained that Bell is designed to help businesses manage customer funds through smart accounts while preparing the network for quantum-resistant security and faster transaction processing.
The testnet activation followed a validator vote scheduled for November 3 at 17:00 UTC. The mainnet vote is scheduled for the same time on November 23, with activation dependent on validator approval.
Stellar Protocol 30 introduces muxed smart contract addresses
One of Bellās main changes is CAP-84, which introduces muxed contract addresses that allow businesses to manage funds belonging to multiple customers through a single smart contract.
Previously, Stellar supported muxed accounts that let exchanges and custodians receive deposits from different customers into one account while identifying individual users through separate IDs.
Smart accounts, which use programmable contracts to control spending permissions, did not have the same capability. Businesses using them generally needed separate contracts to distinguish customer balances.
With CAP-84, a contract address can carry a 64-bit identifier that identifies the intended customer without requiring a separate smart contract for every user.
The new addresses use a format beginning with the letter W, distinguishing them from existing muxed account addresses that begin with M.
When tokens are transferred to one of these addresses, the funds reach the underlying contract while the customerās identifier is recorded in the transfer event.
According to Stellar, exchanges, payment providers and custodians can use the system to manage customer deposits through smart accounts without deploying individual contracts for potentially millions of users.
The change requires wallet providers and other applications that process Stellar addresses to support the new format.
Bell brings post-quantum signature verification to smart contracts
Another major component, CAP-87, introduces support for verifying ML-DSA signatures within Stellarās Soroban smart contract environment.
ML-DSA is a post-quantum digital signature algorithm standardized by the US National Institute of Standards and Technology in 2024.
Unlike existing elliptic-curve signature systems, ML-DSA is designed to resist attacks from sufficiently powerful quantum computers.
Stellar currently uses cryptographic signature schemes including Ed25519, secp256k1 and secp256r1, which could become vulnerable to future advances in quantum computing.
Under Bell, developers can create smart accounts that require ML-DSA signatures before authorizing transactions, allowing wallets and custodians to introduce quantum-resistant spending controls.
The foundation said the verification process runs through Stellar Core because checking ML-DSA signatures requires considerably more computing resources than conventional signatures.
Protocol 30 supports three ML-DSA verification functions corresponding to the algorithmās different security levels.
The feature is the first onchain component of Stellarās Quantum Preparedness Plan, although network-level transaction signatures will continue using Ed25519 until a future protocol upgrade.
Other blockchains have been exploring similar protections. In August, Sui outlined plans to introduce quantum-safe account authentication using NIST-approved signature schemes.
Millisecond ledger timing prepares Stellar for faster processing
Bellās third component, CAP-88, changes how Stellar records the time at which ledgers close.
Currently, Stellar records ledger closing times in whole seconds, which prevents the network from targeting intervals shorter than one second.
The new system introduces millisecond-resolution timestamps, allowing future protocol changes to support more precise ledger closing intervals.
In September, Stellarās Protocol 28 upgrade reduced typical mainnet ledger closing times from approximately 5.7 seconds to five seconds.
CAP-88 does not immediately reduce those times further. Instead, it removes an existing technical restriction, with Stellar Core developers already experimenting with faster ledger processing.
The change introduces a new ledger header format, requiring applications that decode raw blockchain data to update their software.
According to the foundationās upgrade guide, older SDKs may fail to decode Protocol 30 ledgers, while indexers and analytics services must update their XDR definitions.
Existing Soroban contracts can continue operating without modification, although developers must update their tools to use Bellās new features.
Mainnet upgrade scheduled for November 23
Ahead of the mainnet vote, Stellar has released Protocol 30-compatible versions of its Core, Horizon, RPC and Galexie infrastructure software.
Its October 23 upgrade guide listed JavaScript SDK v17.3.0 and Go SDK v0.8.0 among the available developer releases, alongside a release candidate for the Soroban Rust SDK.
Validators have been instructed to install Stellar Core v30.0.0 before the mainnet vote, while exchanges, wallet providers and other infrastructure operators must prepare their integrations for the new ledger format.
The upgrade follows recent developments across Stellarās ecosystem, including VIA Labsā integration of cross-chain messaging between Stellar and Ethereum in late October.
The integration allows Soroban smart contracts to exchange messages with Ethereum-based contracts, supporting applications involving stablecoins, tokenized assets and cross-chain transactions.
Stellarās mainnet upgrade vote is scheduled for November 23 at 17:00 UTC, with the foundation coordinating preparations through its developer community and validator channels.
