Even if the PC is connected via Ethernet, the software emulates fax modem protocols to communicate with the Brother device. This ensures compatibility with standard fax protocols (Group 3 fax).
This is the primary feature, allowing users to send documents directly from their computer to a remote fax machine. brother pc-fax v.3.2
Here is a deep feature covering of Brother PC-FAX v.3.2, broken down by functionality, user interface, and technical integration. Even if the PC is connected via Ethernet,