# The Third Way: Alternatives to PoW and PoS with Lane Rettig

- Speakers: Lane Rettig
- Channel: [Ethereum Denver](https://streameth.org/ethereum-denver)
- Date: 2023-10-07
- Duration: 20:41
- Watch: https://streameth.org/watch/yt-XH5seHS9onI
- YouTube: https://www.youtube.com/watch?v=XH5seHS9onI

## Description

The talk will be broken into three parts. Part I will present some helpful background information for context. It'll introduce the notion of a consensus mechanism with "real world" examples like the ones mentioned above (e.g., driving a car) and a little bit of history from distributed systems and from blockchain. Part II will present the tradeoffs between PoW and PoS: the history, the strengths and weaknesses of each system, with a bit of Ethereum history, Ethereum's motivation for switching, and a discussion of the Merge and how the Eth Beacon chain works. Part III will present some "outside the box" alternatives to PoW and PoS, such as Solana's "proof of history" and Spacemesh/Chia/Filecoin's approach using proofs of space-time. Again, the tradeoffs around these mechanisms will be discussed and they'll be presented in the context of running, production networks. The conclusion will talk about implications for the application layer and for dapp developers: ways in which the consensus mechanism "leaks" through the abstraction boundaries and impacts UX and DevEx, and ways in which applications themselves can make use of consensus.

Lane Rettig