| Accessed from | Sender's address | Recipient's address | Method |
|---|---|---|---|
| Internal network | internal | internal | direct transfer |
| Internal network | internal | external | direct transfer |
| Internal network | external | internal | forbidden |
| Internal network | external | external | forbidden |
| Internet | internal | internal | Sender receives an upload ticket |
| Internet | internal | external | Sender receives an upload ticket |
| Internet | external | internal | get confirmation from recipient |
| Internet | external | external | forbidden |