Right pattern to link Document and Storage

Hello,
This is a thread to discuss options on how to properly have the equivalent of a « File » field in a document linking it to the storage.
What do you suggest?
Simplicity, genericity, security, etc.
Thank you

i have an attribute where i put the file id. either that or i make the file id match the document id

Thank you. How would you maintain consistency on permissions with this? Like make sure that the ones on the document applies to the file?

pass the same permissions when making them