Most networks without fixed infrastructure are based on cloud computing face various challenges. In recent years, different methods have been used to distribute software defined network to address these challenges. This technology, while having many capabilities, faces some vulnerabilities in the face of some common threats and destructive factors such as distributed Denial of Service. A review of various studies shows that in order to eliminate vulnerabilities, we need to combine appropriate defense solutions with the distributed Software Defined Network structure. Therefore, in this study, a general classification of the types of defense solutions against the above attack is presented. Then, while classifying the intrusion detection solutions into two threshold and non-threshold categories, we examined some practical examples of the above solutions. We conclude that the threshold of intrusion detection method exacerbates the vulnerability, and we are required to use non-threshold defense solutions with flat distributed software defined network architecture.