I keep hearing that TPS are not a problem but the latency - its possible to increase TPS but not latency. Why?


All transactions are still submitted to L1 before reaching the sequencer for L2. If this is the case then I still need to wait 15s for my operation to be submitted?

Question from Agora

1 Answer 1


The idea of rollups is to use the L1 to settle the order of operations, and execute the result of those operations off-chain. The idea of optimistic rollups is to delegate the validation of that off-chain to set of rollup validators who stake on the result of operations and can slash each other whenever a problem is detected via a mechanism called the refutation game.

Hence, you can’t have latency lower than the latency of the L1, since that’s what provides the inputs to the rollup. But you can have higher throughput through vertical scalability. While Tezos can run on a Raspberry Pi, there’s no problem with requiring a 128-core machine with 1TB of RAM to keep up with your epic blockchain gaming rollup or whatever.

That’s rollups, pure and simple. But many rollups in the Ethereum ecosystem add an off-chain sequencer to the mix. By forcing transactions to go through a sequencer, the sequencer can provide optimistic results on the execution instantly, before they’re included in the L1. Naively implemented, the sequencer could sensor anyone with impunity; however, it’s fairly straightforward to include a “delayed inbox” that allows anyone to include an operation in the rollup via the L1 in the case of censorship or the sequencer goes down. Smart Rollups don’t ship with a sequencer out of the box since it doesn’t make sense for every application; however, we’re developing that demonstrate how to integrate a sequencer for optimistic low latency in your app.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.