Thanks Karthik for this advice, but it dont work with our XOS devices. I know this tool from my early cabletron days. It seems that this will not work with summit Switches. There was a realy fine Report in Ridgeline included. You could see how Long there is no Traffic on the specified port.
you need to download whole file (save as, not copy and paste from browser). The flexview was tested with Cisco & EnterasysOS & XOS :)