Two HyperTerminal Windows, one DS

Here, we will connect one DS to a computer, using two separate cables; Thus, both ports of the DS (LAN and serial) will be connected to their respective ports on the computer. Follow these steps:

Take a Device Server. If it's a model capable of several serial protocols (such as the DS100-B, who is also RS422/RS485 capable), make sure it's set to RS232.
Power it on.
Take a serial cable and follow the steps described in Establishing a Serial Connection with a Device Server. Return to this section once done.
Now, connect the same Device Server to the same computer using a cross LAN cable, or to the network segment the computer currently belongs to (using a straight cable to a hub, etc).
Follow the steps described in Establishing a TCP/IP Connection with a Device Server or in Establishing a Connection Through a Virtual Serial Port. Return to this section once done.
That's it! Now, whatever you type in the window connected to the serial end, will show up in the window connected to the network end. And vice versa. If you can see this, you've performed all of the above correctly!