In this work, we elaborate on the critical missing gaps in DDoS defense evaluation and propose a new evaluation platform to help produce the missing defense analytics. To identify the impact of a defense solution in realistic network settings, our platform offers to emulate a mini Internet topology with realistic IP address space allocation and generate representational, closed-loop background traffic specific to particular networks. As such, our platform fulfills the prominent missing gaps in current DDoS research. In the end, we conduct some experiments to demonstrate the correctness and efficiency of our platform.