Amazon.com: Mini Industrial 4 Port 10/100/1000Mbps Gigabit Ethernet POE + Switch with SFP Port Din Rail/Wall-Mount 4 Port 10/100/1000BASE-T RJ45 + 1 Port 100/1000FX (SFP) Support 12-48V DC : Electronics
Amazon | Industrial Ethernet on the Plant Floor: A Planning and Installation Guide | Lounsbury, Robert | Networks, Protocols & APIs