Traditional networking is being progressively replaced by Software Defined Networking (SDN). It is a new promising approach to designing, building and managing networks. In comparison with traditional routed networks, SDN enables programmable and dynamic networks. Although it promises more flexible network management, one should be aware of current and upcoming security threats accompanied with its deployment. Our goal is to analyze SDN accompanied with OpenFlow protocol from the perspective of Distributed Denial of Service attacks (DDoS). In this paper, we outline our research questions related to an analysis of current and new possibilities of realization, detection and mitigation of DDoS attacks in this environment.