RFP 11 - Pre-Confirmation Mechanisms

Researcher: TBD


Pre-confirmation for rollup blocks offer an opportunity to speed up transactions for users and protocols. Yet, existing pre-confirmation mechanisms are largely in their early development stages. More work must be done to understand how pre-confirmations can be best implemented for rollups in a manner that is secure, efficient, and fast.

The present research aims to contributes the following:

  • An understanding of the need (or lack thereof) for sequencers providing pre-confirmations to also provide a stake, including what tools/infrastructure/staking amounts are needed

Background & Problem Statement


Core background concepts/definitions are as follows:

Pre-Confirmations (preconfs):

Pre-confirmations are a growing concept in the rollup space. Many rollups offer pre-confirmation of their blocks before they are committed, i.e. before they are sent down to a data availability (DA) layer. Some mechanisms for enabling pre-confirmation of rollup blocks are as follows:

  • Soft finality is guaranteed over rollup transactions before they are posted to a DA layer based on the consensus between node operators on a shared settlement layer or sovereign rollup. This only works for rollups where transaction settlement occurs on a separate layer from the DA layer.
  • Sequencers are required to post collateral that can be penalized by the rollup if they do not post the block to the DA after a certain timeframe.

Technical details of various pre-confirmation models can be found in the references attached at the end of this document.

Pre-confirmations act to speed up the user experience. Based rollups, for example, can offer pre-confirmations. Justin Drake of Ethereum Research states that Based preconfs offer a competitive user experience for based sequencing, with latencies on the order of 100ms.

However, pre-confirmations have a limited security model, as there is a limited ability to make guarantees to many participants simultaneously.

Problem Statement

The problem here is that research and development into pre-confirmations for rollup blocks are in their very early stages. A number of models have been proposed (see attached references), yet there is little data available on how they operate in practice.

Thus, the question that this research aims to address is as follows:

  • Do sequencers need to be restaked to issue pre-confirmations?
  • If yes, what tools/infrastructure/stake amount is needed?

Plan & Deliverables

Expected outputs/deliverables are as follows:

  • An understanding of the need (or lack thereof) for sequencers providing pre-confirmations to also provide a stake, including what tools/infrastructure/staking amounts are needed

The plan for achieving this output is outlined below:

Experiment: Develop a model for the stake/process required for sequencers providing pre-confirmations

This will be done by mathematically determining the required stake for a sequencer (which may be 0). If required stake is a nonzero number, we will analyze existing pre-confirmation models to determine if/how they handle sequencer staking. We will use this, in combination with our own mathematical model for sequencer stake, to design a model for sequencers providing pre-confirmations to also provide an adequate stake.


How to Participate

If you’re a researcher who believes that you would be a good fit to contribute to any of the Composable RFPs, please reach out to Composable’s Lead Research Associate, Sydney Sweck, at sydney@composable.finance. In the email, be sure to include:

  • The RFP number(s) you’d like to contribute to
  • Your relevant background experience
  • How you think you could contribute to the research