> For the complete documentation index, see [llms.txt](https://doc.cess.network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.cess.network/ref/data-lifecycle.md).

# Data Lifecycle

User data uploaded to the CESS network undergo the following lifecycle. We will cover them in-depth here.

* [**Data Upload**](/ref/data-lifecycle/upload.md): Through CESS clients or gateways, users upload data to the rented storage space. CESS uses erasure codes to store the data on multiple storage nodes with 1.5 times redundancy.
* [**Data Download**](/ref/data-lifecycle/download.md): Data on CESS is available for download. The file meta information is saved on-chain. Users can use a client or gateway to retrieve the data locally.
* [**Data Deletion**](/ref/data-lifecycle/delete.md): CESS node deletes the data upon their owner requests and intelligently handles replacing active data back with idle data.
* [**Data Restore**](/ref/data-lifecycle/restore.md): CESS ensures the integrity of user data through a storage challenge mechanism. When a data block is found to be lost, CESS immediately repairs the data block.
* [**Data Audit**](/ref/data-lifecycle/audit.md): CESS has developed a series of audit algorithms and reward mechanisms to ensure the data stored in the storage nodes is honestly and objectively served.