The move towards modularization in blockchain has become an inevitable trend. The execution layer, settlement layer, and data availability layer each perform their own functions, which sounds perfect. But in practice, the questions arise—how can these independent modules collaborate efficiently? Can costs be reduced? Is security guaranteed?

This "intermediate link" issue has recently attracted the attention of many projects. Take Celestia as an example; it addresses the problem of data "existence," ensuring that data is published and verifiable. It sounds powerful, but this is different from whether the data is "useful" or not.

Downstream validators, users, and infrastructure operators of Rollups or application chains need more than just "data being there." They need to quickly find, access, and verify the specific data they require. If this process is slow, the entire chain's certainty and user experience will suffer. Simply put, it's the "last mile" problem—how to smoothly retrieve data from the DA layer.

Some projects see this opportunity and position themselves as the "central nervous system" of the modular stack. Not just a database, but aiming to create a unified data interface. What does this mean? It’s about hiding the complexity of DA layers like Celestia, EigenDA, and potentially future Ethereum DankSharding. Upper-layer applications only need to call standardized interfaces to perform data retrieval and verification.

This abstracted design, in theory, can reduce the integration costs for application chains and Rollups. No need to adapt to each peculiar DA layer interface—one unified window handles it all. In the long run, the value of such infrastructure might be underestimated—it’s like network protocols, the more fundamental they are, the easier they become standards. Whether they can establish a foothold in the wave of modularization depends ultimately on how well this solution performs in real-world applications.