The only Smartbits application that came with the Spirent SmartBits 600 was a demo copy of Smartflow. Indeed, if this worked, it would be an excellent way to measure frame loss and throughput of our Vyatta router. However, I can only get it to report 20% packet loss on the first iteration and 100% loss for all subsequent iterations whether you step the load down or up and regardless of the initial loading. That doesn't make sense, unless there is a limitation on the demo copy. So I have given up for now. This program is not marketed any more. It is part of a new SmartBits module which we don't have. And the test methods in SmartWindow don't work either. Too bad.