Serial communication protocol has been around since the late 1960s but it is still very much the preferred way of serial data exchange with specialized laboratory and industrial equipment. However, the trend with modern computers seems to be towards omitting the physical serial port. This makes it difficult to connect serial ports over Ethernet networks. Fortunately, this can be overcome with the use of third-party tools that allow you to connect and share your serial devices across Ethernet.

The Modern Way Of Sharing Serial Over Ethernet

Serial over Ethernet software will emulate a serial port on a computer that does not have one. This is achieved by creating virtual instances of actual serial ports that allow you to connect to the remote devices as if they were physically connected to your computer.

Serial to Ethernet Connector (SEC) allows the sharing of real and virtual serial ports over the Internet or LAN.

The software should be installed on the machine where the device is connected. That machine then becomes the server. Multiple remote computers or so-called clients are then able to access and communicate with the connected device on the server.

How To Use Serial Over Ethernet Software

  • Download the SEC software and install it on the server and client machines.
  • Launch the application on the server. Select the “Server connection” tab and enter the required parameters for your network settings. When done, click “Create a connection”.
  • To configure the clients, start the application on the client. Click on the “Client connection” option in the main menu. Configure the client as per your required settings and then confirm by clicking “Create connection”.

The server is the machine that has the physical serial device attached to it and that you want to make accessible to other machines.

The client is the remote computer on the network that will connect to and access the serial device on the server.

Once both server and client(s) are set up, your client machines will have full access serial over Ethernet on Windows as the shared serial device appears in the client’s Device Manager.

Sharing Serial Over Ethernet On Linux

Linux offers native solutions for sharing remote serial ports. Netcat (NC) is a command-line utility that facilitates reading from and writing to different connections on your network using TCP or UDP.

An example of how to connect serial ports over Ethernet on Linux simply use the following:

netcat www.example.com port /dev/ttyS0 

Using this method requires a new instance of netcat for each new connection. To overcome this you can have netcat persist over connections by creating a xinetd service. An example of the required configuration is as follows:

service testservice { port = 5900

socket_type = stream

protocol = tcp

wait = yes

user = root

server = /usr/bin/netcat

server_args = “-l 5900 < /dev/ttyS0”

}

Change dev/ttyS0 to your required serial port. Use sty or setserial commands to configure your COM port parameters like baud rate, bits-per-second (bps), parity, etc.

Hardware Devices For Serial Over Ethernet Sharing

A serial to Ethernet converter is a cost-effective solution to overcome the lack of physical serial ports. It will let you connect multiple serial devices over Ethernet as with cable to your computer without the need to physically plug in the devices before sharing them.

The serial to Ethernet extender solves two problems. Firstly, if your local machine does not have a serial interface and you simply need to connect a serial device to it, and secondly – being able to share serial equipment over the Ethernet to other remote computers