BlockBeats news: On January 4, Delphi Digital posted on the X platform stating that Solana is preparing a major upgrade called Alpenglow. This upgrade represents a complete re-architecture of the consensus mechanism, aiming to achieve sub-second finality by replacing Tower BFT and the Proof of History (PoH). Alpenglow introduces two new protocol components: Votor and Rotor.
Votor replaces the incremental voting rounds of Tower BFT with a lightweight voting aggregation model. Validators can aggregate votes off-chain before submitting final confirmation, enabling blocks to achieve finality within 1 to 2 confirmation rounds. This improvement reduces the theoretical finality latency to 100–150 milliseconds, a reduction of about 100 times compared to the original 12.8 seconds. Votor achieves final confirmation through two parallel paths: if a proposed block receives support from more than 80% of the total staked weight in the first round, a fast confirmation is triggered and takes effect immediately; if the support rate in the first round is between 60% and 80%, a slow confirmation is triggered, requiring a second round of voting with more than 60% support to finalize the block.
Rotor has restructured Solana's block propagation layer. Previously, the Turbine propagation network relied on multi-hop relays with variable latency, while Rotor introduces staking-weighted relay paths that prioritize bandwidth efficiency. Validators with high staking and reliable bandwidth will become core relay points. Simulation data shows that under typical bandwidth conditions, block propagation can be completed in as fast as 18 milliseconds. This upgrade is expected to be rolled out gradually, with an initial launch anticipated between early and mid-2026.