> ## Documentation Index
> Fetch the complete documentation index at: https://docutrack-docs.icpitalia.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Document Upload

> How Docutrack is implemented

When a document is to be uploaded, a symmetric secret key for the document is created in the (potentially unregistered) user's frontend.

In the example above, this user is called Bob. The document is encrypted with this secret key.

<Frame>
  ![file upload first step diagram](https://github.com/icp-hub-it/ic-docutrack/raw/main/docs/images/upload_step1.png)
</Frame>

As a next step, the frontend obtains the public key of the registered user who created the request link, Alice, from the backend.
The document’s secret key is encrypted for Alice.

<Frame>
  ![file upload second step diagram](https://github.com/icp-hub-it/ic-docutrack/raw/main/docs/images/upload_step2.png)
</Frame>

Both the encrypted document and the encrypted secret key are sent to the backend where they are stored.

<Frame>
  ![file upload third step diagram](https://github.com/icp-hub-it/ic-docutrack/raw/main/docs/images/upload_step3.png)
</Frame>