# Storage Layer and Cross-Chain

### <mark style="color:orange;">Storage Layer: Data Availability and AI Data Marketplace</mark>

* **Decentralized storage integration** (e.g. IPFS, Arweave) for permanent and tamper-proof data storage.
* **Zero-copy data availability (DA)** supporting external modules like Celestia and EigenDA to improve Rollup data reuse efficiency.
* **AI Data Marketplace:** Users can upload training datasets on-chain, mint them as NFTs for licensing and royalty distribution—providing **trusted data sources** for AI applications.

### <mark style="color:orange;">Cross-Chain and Interoperability</mark>

* **Cross-chain protocol support:** Compatible with IBC, LayerZero, Wormhole for multi-chain interoperability.
* **Payment anchoring:** The USDA stablecoin serves as the core anchor asset for cross-chain payments and settlements.
* **Cross-chain calls and message bus:** A unified API interface for cross-chain contract calls, event subscriptions, and state synchronization.


---

# 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://apchain.gitbook.io/apchain-docs/technical-architecture/publish-your-docs.md?ask=<question>
```

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.