Avalanche (consensus)
A family of leaderless, metastable voting protocols that eCash layers on top of Nakamoto consensus to finalise blocks and, since 2025, transactions.
The wiki's angle: Avalanche is Amaury Séchet's answer to the hash war that split Bitcoin Cash. Instead of trusting hashpower alone, eCash nodes with stake vote on the tip, which Séchet says makes many 51% attacks “just not possible”.[3][4]
The protocol
The 2019 arXiv paper by “Team Rocket”, Maofan Yin, Kevin Sekniqi, Robbert van Renesse and Emin Gün Sirer introduces “a family of leaderless Byzantine fault tolerance protocols” built on metastability[1]. Asked why eCash chose it, Séchet said: “Because it's fast and it's simple. And it's actually correct, because many of the alternatives that are out there are unsound”[2].
On eCash
On S17 E19 Amaury Séchet described Avalanche as a consensus layer added on top of the BCH-derived protocol that “can make decisions in seconds, typically less than two seconds”[3]. He said it produces no auditable record, “which is why we don't want to remove the Nakamoto consensus”[3]. Bitcoin Takeover's eCash article dates block post-consensus to 14 September 2022 and transaction finality to 15 November 2025, block 923,347[4].
Staking
The eCash article says staking requires each staked coin to hold at least 100 million XEC and stay unmoved for 2,016 blocks, on an always-on Avalanche node, and that since November 2023 10% of each block goes to one staker chosen by lottery[4]. Kurt Wuckert Jr. discussed Avalanche pre-consensus and his disagreement with Séchet on S17 E39[5]. See eCash (XEC).
References
- primaryTeam Rocket, Yin, Sekniqi, van Renesse, Sirer, “Scalable and Probabilistic Leaderless BFT Consensus through Metastability”, arXiv:1906.08936 [archived]
- episodeS17 E19: Amaury Séchet on why Avalanche▶ listen at 2:41:22timestamp transcript-derived, pending a listen [archived]
- episodeS17 E19: Amaury Séchet on Avalanche on top of Nakamoto consensus▶ listen at 46:17timestamp transcript-derived, pending a listen [archived]
- btkeCash (XEC): The Fork That Taxed Itself (BTCTKVR: Forks!) [archived]
- episodeS17 E39: Kurt Wuckert Jr. — Avalanche pre-consensus and the fight with Amaury▶ listen at 1:05:56timestamp transcript-derived, pending a listen [archived]