关键词: 分布式拒绝服务攻击 单边连接密度 相对值特征（RVF）向量 超球体多类支持向量机（HSMC-SVM）

Abstract: For defending DDoS attacks effectively, the more information about the attacks is required. However, the present methods only stress the existence of attacks, so they are hard to indicate the attack protocols, attack density and attack patterns at one tim

Key words: Distributed denial of service attack, One-way connection density, Relative volume feature vector, Hypersphere multi-class svm