Research on the Characteristics and Blocking Realization of Skype Protocol

For end-to-end encryption and special communication protocol-based Skype system, it is not feasible to recognize the Skype protocol by using traditional port-based or payload-based identification methods. By detailed analysis of Skype protocol, this paper explores the general characteristics and special behavior characteristics under certain circumstances of Skype application and proposes a connection tracking-based strategy that can efficiently recognize Skype application and in further step block it. The experimental result indicates that the proposed method can efficiently block the current popular version of the Skype application, thus, achieve the high security of network.