NTT Communications Huawei Technologies Co., Ltd. Huawei Technologies Co., Ltd. Microsoft Comcast, Inc. Charter Communications As DDoS attacks evolve rapidly in the aspect of volume and sophistication, cooperation among operators has become very necessary because it gives us quicker and more sophisticated protection to cope with the varius DDoS attacks. This document describes possible mechanisms which implement the cooperative inter-organization DDoS protection by DOTS protocol. The described data models are intended to cover intra-organization and inter-organization solutions.