Distributed denial of service (DDoS) attacks on the Internet have become an immediate problem. As DDoS streams do not have common characteristics, currently available intrusion detection systems (IDS) can not detect them accurately. In this paper, we propose a distributed approach to detect distributed denial of service attacks by coordinating across the Internet. Unlike traditional IDS. we detect DDoS at the intermediate network. Our scheme uses a nonparametric point detection method to improve the detection accuracy at each individual node. Then, a gossip based multicast mechanism is used to exchange information between the individual nodes to further improve the detection accuracy. To provide reliable, rapid and widespread dissemination of attack information, the system is built as an overlay network on top of the internet. Initial results using simulation illustrate that the proposed approach is both efficient and feasible.