FlexPendant C# app to connect with an external device with TCP/IP


We have a running aplication developed with the FlexPendant SDK and C#.
We can connect to an external device and show relevant information in the FlexPendant console using a TcpClient object and the Service Port.
The IP of the equipment is in the range 192.168.126.x 
The FlexPendant IP is the default:
The fisical connection we use is:  

But really, what we want is the following device connection:

Is this possible ?
Can the FlexPendant application in this scenario communicate with an external device?
Which connector/port of the robot controller to use ?
Is any configuration necessary? Any license? (in the robot controller)

Thanks !!