> For the complete documentation index, see [llms.txt](https://docs.xyo.network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.xyo.network/about-xyo/core-paradigms-of-xyo/off-chain-data-on-chain-proof/off-chain-data-xyo-layer-one.md).

# Off-Chain Data XYO Layer One

XYOL1 provides multiple mechanisms that enable off-chain data handling while maintaining on-chain trust through cryptographic proofs.

### Layer One Features

#### [Bound Witnesses](broken://pages/ZqlVsvoRlxTIq1Gpys9b)

Bound Witnesses allow two devices to mutually sign and record an interaction without sending the full event to the blockchain. The interaction is proven by shared, signed cryptographic evidence—**not by broadcasting full data**.

#### [Bearer Proofs](broken://pages/O4xAGFFYZ6LURfVJOLio)

Bearer Proofs are small, cryptographically secure references that prove a piece of data belongs to a known set—**without revealing or transmitting the full set**. This allows users to verify claims without sharing underlying records.

#### [Framing Cursors](broken://pages/eIyVnMmlZBymn9ICKsz9)

Framing Cursors enable efficient access to off-chain data by marking *where* to look within a larger structure. They let you provide minimal proof of inclusion across specific frames of the blockchain—again, **without full-chain scanning**.

#### [Bound Witness Trees](#dbound-witness-trees)

Instead of validating transactions one by one, Bound Witness Trees let XYO aggregate many events into a single hash. This hash is stored on-chain. If validation is needed later, the full tree can be reconstructed and proven off-chain—**only the hash lives on-chain**.

### Real-World Example

A supply chain logs a sensor reading for perishable goods (e.g., vaccine temperature). The full sensor data is too large and sensitive to store publicly.

#### **With XYO**

* The sensor logs the reading off-chain.
* A Bound Witness is generated to prove the reading occurred and was valid.
* A hash of that reading is recorded on-chain via a Bearer Proof or within a Bound Witness Tree.
* At any point, a verifier can validate the reading’s authenticity by comparing it against the on-chain proof—without ever seeing or revealing the full data.