# Data Availability In the context of rollups, Data Availability refers to the ability to reconstruct L2 state from the data published on durable storage, commonly stored on L1 (such as Ethereum). Data availability is crucial for asset security, particularly in the event of sequencer failure. Historically, the cost of data availability has often dominated the gas consumption of rollups. It is encouraging to note that with the activation of EIP-4844 in the Dencun hard fork, this situation has been significantly [improved](https://vitalik.eth.limo/general/2024/03/28/blobs.html). However, uploading data onto blobs may still cost around $0.01 per request, which could become expensive given Vessel's capability to scale up to 1000 TPS. An alternative to directly committing transaction data onto L1 is to adopt a third-party data availability service or rely on an external Data Availability Committee to store data and provide it on demand. This architecture, known as [Validium](https://ethereum.org/en/developers/docs/scaling/validium/), has become a prevalent choice for deploying rollups and application chains. Another important consideration for Data Availability is privacy. Trading platforms have different privacy requirements compared to public blockchains, and current Data Availability solutions typically assume that the data provider has access to the entire data history. Vessel Lab is exploring ways to achieve Data Availability while maintaining privacy through Multi-Party Computation (MPC) techniques. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://vesselfinance.gitbook.io/vessel/technical-deep-dive/data-availability.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.