http://protonmailrmez3lotccipshtkleegetolb73fuirgj7r4o4vfu7ozyd.onion/blog/centalized-vs-p2p-protondrive
The classic centralized storage model is used by all the “big name” providers, including Google Drive, Dropbox, and Apple iCloud. Users’ data is stored on physical servers that are owned and operated by the cloud provider. This means that when you upload files to a centralized storage account, you upload them to a server center run by the service provider, and download them from the server center when you want to access them (or when they are synced across your devices).