TL;DR
- Solana began testing the Alpenglow upgrade on its public testnet, which would reduce transaction finality from ~13 seconds to 0.15 seconds.
- Alpenglow replaces the TowerBFT system with a voting protocol called Votor, which allows blocks to be closed in one or two validation rounds.
- Validators participating must run Agave 4.3, maintained by Anza; Firedancer and Frankendancer do not yet support the Alpenglow test.
The public testnet of Solana began hosting the Alpenglow upgrade, a modification to the consensus mechanism that, according to its developers, would reduce the transaction finality time from approximately 13 seconds to 0.15 seconds.
Finality is the point at which a transaction becomes irreversible, and critical operations depend on it, such as deposit crediting on exchanges, fund releases on cross-chain bridges, and payment confirmation in commerce.
Alpenglow on the Testnet: Solana’s Rules Are Changing
Solana currently uses a consensus system called TowerBFT, in which validators record their votes directly on the blockchain and must accumulate enough confirmations across 32 slots before a block is finalized.
Alpenglow replaces that scheme with a voting protocol called Votor, where validators send votes directly to each other and can agree on a block after one or two rounds, eliminating the long chain of on-chain votes that currently causes the delay.
For users, the transition will not involve changes to wallets or to the way funds are sent. Applications will continue executing transactions in the same way they do today.
Alpenglow has been operating for more than four months on a smaller network created specifically for the upgrade. The move to Solana’s testnet allows verification of whether the set of computers and services already running the blockchain can migrate together without issues.
Only Agave Will Be Available
Validators participating in this phase need to run Agave 4.3, the network’s main software maintained by Anza, one of the companies responsible for developing the protocol. Anza recommended that version to all validators on the mainnet, after deploying it in stages among operators that first control 10% and then 25% of Solana (SOL) tokens used to secure the network.
Firedancer and Frankendancer, the two alternative validation programs developed by Jump Crypto to reduce dependence on a single software, do not yet support the Alpenglow test. Their absence means the first migration will run entirely through Agave.
September 28 appears on Anza’s schedule as a tentative date to activate the features included in Agave 4.3 on the mainnet, although it is not a confirmed launch date.
