--- title: BNB Chain ticker: BNB category: Layer 1 written_by: GPT-6-Astra high status: ai-fact-checked checked: 2026-10-31 checked_by: GPT-6-Astra high updated: 2026-10-31 --- # BNB Chain BNB Chain is a blockchain ecosystem that includes BNB Smart Chain (BSC), opBNB, and the Greenfield storage network. BSC supports Ethereum Virtual Machine-compatible smart contracts and uses BNB for execution fees and staking. The ecosystem also previously included BNB Beacon Chain, whose functions were migrated through the Chain Fusion programme.[^ecosystem][^bsc][^fusion] | | | |---|---| | Native asset | BNB | | Smart-contract base chain | BNB Smart Chain | | BSC consensus | Proof of Staked Authority | | Other components | opBNB and BNB Greenfield | | Retired component | BNB Beacon Chain | ## Execution and validators BSC is a separate blockchain with its own validators, even though its execution environment supports Ethereum tooling. Its consensus combines stake-based validator selection with a limited set of authorities taking turns to produce blocks. EVM compatibility does not mean that Ethereum validators secure BSC transactions.[^bsc] As of October 2026, the validator documentation describes daily elections for 45 active validators: 21 Cabinets and 24 Candidates. Each epoch draws 18 from the first group and three from the second to form the 21-validator consensus set. Staking rank therefore influences both selection and participation; “45 active validators” does not mean all 45 produce blocks in every epoch.[^validators] ## Chain Fusion Chain Fusion moved Beacon Chain functionality to BSC and retired Beacon Chain. Native staking on BSC allows delegators to stake without first moving BNB to the older network. The current architecture should therefore be distinguished from earlier descriptions of two simultaneously active chains dividing execution from staking and governance.[^fusion][^staking] The post-Fusion documentation describes the shutdown of Beacon Chain transaction processing and its normal cross-chain communication with BSC. Recovery of eligible remaining assets uses a separate migration process. It explicitly warns that BEP-2 or BEP-8 assets not bound or mirrored to BSC cannot be recovered through that process. BNB Chain's later notice says the hosted recovery tool was discontinued on 1 July 2026 and replaced by an open-source tool run locally; its workflow still requires an approval-server signature.[^recovery][^self-service] ## Security incidents and upgrades In an October 2022 incident, an attacker exploited BSC Token Hub, the bridge between Beacon Chain and BSC. BNB Chain's account reported 2 million BNB withdrawn through forged proofs. The team said it contacted validators individually to coordinate a suspension of BSC. The incident demonstrated both a bridge-verification failure and the network's ability to coordinate an emergency halt.[^incident] BNB Chain's August 2026 upgrade announcement described Fermi as having reduced BSC's block interval to 0.45 seconds, followed by Osaka/Mendel changes intended to improve operation at that pace. It scheduled Pasteur for 25 August, with changes to bridge signature verification, validator key rotation, and block utilisation. The announcement's throughput figures were testnet benchmarks, not measurements of ordinary mainnet traffic. A September follow-up states that Pasteur activated on 25 August 2026.[^pasteur][^post-pasteur] As of 31 October 2026, the release notes identify v1.8.1 as a Chapel testnet release for Jenner, with no mainnet activation scheduled in that release. Its listed changes include a compliant-asset token standard, a payment lane reserving block capacity, and millisecond timestamps. Those release notes do not establish that these features are already active on mainnet.[^jenner] ## Governance and dependencies The validator set, staking rules, and bridge verification are separate parts of the system's security. Fast blocks and compatibility with Ethereum applications do not remove those dependencies. The 2022 bridge incident and later verification upgrades provide concrete examples of why application users must distinguish execution compatibility from consensus and cross-chain trust.[^bsc][^incident][^pasteur] ## See also - [Binance](binance.md) - [Ethereum](ethereum.md) - [Proof of stake](proof-of-stake.md) - [Blockchain bridge](blockchain-bridge.md) ## References [^ecosystem]: BNB Chain. *BNB Chain website*, chain navigation and Beacon Chain sunset status. [^bsc]: BNB Chain documentation. *BSC introduction*. [^validators]: BNB Chain documentation. *BSC Validator Overview*. [^fusion]: BNB Chain documentation. *BNB Chain Fusion*. [^staking]: BNB Chain documentation. *Staking*. [^recovery]: BNB Chain documentation. *Post-Fusion FAQ*. [^incident]: BNB Chain (2022-10-07). *BNB Chain Ecosystem Update*. [^pasteur]: BNB Chain (2026-08-14). *Pasteur Hardfork Arrives on BSC Mainnet on August 25*. [^self-service]: BNB Chain documentation. *Token Recovery Tool Sunset — Phase 3 (Self-Service)*. [^post-pasteur]: BNB Chain (2026-09-14). *Post-Pasteur Hard Fork: BSC Packs 28% More Gas Per Block With More Scale Ahead*. [^jenner]: BNB Chain. *Release Notes*, v1.8.1 (2026-10-16).