Anza activates Alpenglow on Solana, targeting 150ms finality
Anza activated Alpenglow on Solana mainnet on Oct. 21, replacing TowerBFT and targeting finality in about 150 milliseconds, down from roughly 12.8 seconds.
The Blocktape Editors 2 min read 5dfdcb
Anza activated its Alpenglow consensus protocol on Solana mainnet on Oct. 21, replacing TowerBFT and targeting transaction finality in about 150 milliseconds, down from roughly 12.8 seconds. The change alters how validators agree that transactions can no longer be reversed.
Alpenglow took over at slot 459,653,000 at about 14:00 UTC, according to Anza’s announcement. The firm said the network’s validators retired TowerBFT, which Solana had used since its 2020 launch.
How does Alpenglow change transaction finality?
Alpenglow replaces TowerBFT’s two-step confirmation process with a voting protocol called Votor. Validators send votes directly to one another and aggregate them into certificates, rather than recording votes as transactions on the blockchain, according to the Solana Foundation’s Alpenglow guide.
Votor can finalize a block in one or two rounds of voting. The Foundation says a block can finalize in one round when at least 80% of stake votes to notarize it; otherwise, a second round can complete finalization under different stake thresholds.
Is 150 milliseconds a measured mainnet result?
The 150-millisecond figure is a target, not a guaranteed constant. The Solana Foundation says actual finality depends on stake distribution, network latency and whether a block finalizes in one or two rounds.
Anza describes the change as reducing finality from about 12.8 seconds to roughly 150 milliseconds. That is the point at which a transaction can no longer be reversed; it is distinct from the time taken to produce a block.
What changes next for Solana?
Alpenglow removes validator vote transactions from blocks, while transaction execution and fees remain unchanged, the Foundation says. Applications that count or stream block data may need to adjust how they interpret blocks and transaction totals.
Anza’s next planned consensus-related change is Rotor, which is intended to replace the system that spreads block data across the network. The Foundation says Rotor is planned for a later release and has no scheduled activation date.
Source material
- Anza’s announcement — prnewswire.com
- Solana Foundation’s Alpenglow guide — solana.com