Thread by @epolynya

One of the most underappreciated benefit of rollups vs high-TPS L1s is efficiency of liveness, censorship resistance and finality. In the latter, the consensus protocols have to offer permanent CR, L, and safety. In rollups, you only need ephemeral CR, L for a few minutes.

1/8

ORs generally settle every couple of minutes, SNARK rollups like Loopring ~12 minutes, STARK rollups like dYdX ~1 hour. It could be longer if they are less active, but as activity ramps up and the tech matures, I'd expect these times to decrease rapidly, eventually few sec.

2/8

Rollups that want to maximize ephemeral CR & L, can run proof-of-stake consensus just like their MC ancestors. However, they only need to do this for a few minutes instead of forever! As a result, they can be far more efficient. Which also enables more rapid finality.

3/8

This efficiency manifests itself by requiring way fewer validators overall vs high-TPS L1s, even though per unit time it's the same. Alternatively, they can trade-off efficiency by having the same number of validators, but per unit time far greater CR & liveness properties.

4/8

But where things get fascinating is you can do much better than proof-of-stake, which is very inefficient. You can do sequencer auctions, rotation mechanisms, combine rotation with BFT etc. There'll be a ton of innovation, with efficient frontiers invented well beyond PoS.

5/8

Even if a rollup has a centralized sequencer and fails, you're not actually trading off CR & L forever - just losing real-time access ephemerally and waiting a few minutes. You can withdraw your funds from L1/SL, and in some rollups even make transactions.

6/8

The final piece of the puzzle and the really hard part is safety: this is done by verifying on whatever's the most secure settlement layer. Both combined, rollups get you rapid finality, max CR & liveness, combined with maximum safety which high-TPS L1s necessarily trade-off

7/8

Finally, even as we get innovative decentralized sequencer protocols for rollups over time, there's still a real use case for having a centralized sequencer, or maybe PoA type federated sequencers.

This thread might be controversial, let's see.

8/8

https://twitter.com/epolynya/status/1455037920633520130

Correction: If all sequencers fail, in most rollups you can withdraw your funds immediately. What you'll lose out on is convenience and cost, but hopefully we'll see better infrastructure around that in the future. If you're censored, then yes, it's a bit more complicated.