StarTech.com 1 Port RS232 Serial Ethernet Device Server - PoE Power Over Ethernet - Serial over IP Device Server Adapter - PoE-Powered (NETRS2321POE) - device server

This RS232 Serial Ethernet Device Server allows you to install your RS232 serial devices anywhere on your TCP/IP Ethernet WAN/LAN, and still access them as if they were right beside you - even if the connection is established through an Internet connection!
The serial interface converter provides easy serial control even at the longest distances, allowing access to the remote serial ports from within your local computer Windows device manager.
The RS232 Serial Ethernet Device Server is designed to function seamlessly with your other serial ports for totally transparent operation. Your serial equipment – card scanners, access keypads, bar code scanners, and more – will operate as smoothly as if the serial ports were right inside your computer. For industrial automation, security, Point of Sale, or any time you need reliable, long-range serial communications, the Device Server delivers superior performance in any environment.
A practical solution for industrial RS232 serial applications, the Ethernet/serial device server supports PoE (Power over Ethernet) when connected to a PoE switch, hub, or other device - eliminating the need to use an external power supply and in turn making it easier to situate the device server as needed.