Anza researchers publish Alpenglow, a new consensus protocol for Solana

Solana/Alpenglow consensus

Anza researchers presented Alpenglow on May 19, 2025, a consensus redesign replacing TowerBFT and Proof of History with Votor (voting/finalization) and Rotor (data dissemination). Median finality drops from 12.8 seconds to approximately 150 milliseconds in simulations.

• Votor achieves finalization in one round if 80% of stake participates, or two rounds at 60% participation; Rotor uses erasure-coded data with single relay layer versus multi-layer trees.
• 150 ms median finality with some cases reaching 100 ms—comparable to Web2 infrastructure latency.
• Protocol tolerates 20% adversarial stake plus 20% non-responsive stake.
• Alpenglow represents a fundamental redesign of Solana's consensus layer, not an incremental upgrade.