MODBUS plus diagnostic software/hardware

What options exist there to diagnose a MODBUS plus network under Windows GUI? Say, similar to Comprofibus or Netpro from Siemens.
What hardware are needed for such diagnosis?

It is my impression that Modbus Plus uses an adapter 'modem' box running from a serial port or a USB port. The adapter 'modem' comes with driver software. Whatever diagnostics come with the adapter driver are available for use.

Check out the manual for such an adapter here:
http://www.global-download.schneide...525787900146868/$File/35011984_k01_000_00.pdf

An overview of its capabilities is here:
http://www.guilleviniag.com/downloa... & Networking/New USB Converters & Cables.pdf

There are some screen shots of diagnostics.

I've never used one and can't help you out beyond the link to the manual.