Why Recently, my fiber-to-the-home (FTTH) connection changed from a slighly easier DHCP based setup to an additional required authentication step using PPPoE to connect to the Internet. The advantage is that, for IPv4, I no longer have to use double-NAT, as my own OPNsense firewall can directly get the (dynamically assigned through PPPoE, but statically allocated at the ISP end) IPv4 WAN address instead of the previous ISP router in between that then handed out transfer net non-routable IPv4 addresses via DHCP.