> For the complete documentation index, see [llms.txt](https://qi-blockchain.gitbook.io/qie-oracle/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://qi-blockchain.gitbook.io/qie-oracle/security-and-reliability/security-and-data-integrity.md).

# 🔐 Security and Data Integrity

* Only **authorized nodes** are permitted to submit updates to the Oracle contracts.
* Each update is **cryptographically signed** to guarantee authenticity and prevent tampering.
* Smart contracts consuming oracle data can implement **sanity checks**, such as limiting the maximum allowed price deviation per update, to reject suspicious or erroneous values.

These measures together ensure the **security, reliability, and trustworthiness** of QIE Oracle price feeds.