Biblio

Security policy is widely used in network management systems to ensure network security. It is necessary to detect and resolve conflicts in security policies. This paper analyzes the shortcomings of existing security policy conflict detection methods and proposes a B+ tree-based security policy conflict detection method. First, the security policy is dimensioned to make each attribute corresponds to one dimension. Then, a layer of B+ tree index is constructed at each dimension level. Each rule will be uniquely mapped by multiple layers of nested indexes. This method can greatly improve the efficiency of conflict detection. The experimental results show that the method has very stable performance which can effectively prevent conflicts, the type of policy conflict can be detected quickly and accurately.

Software-Defined Network (SDN) is a novel architecture created to address the issues of traditional and vertically integrated networks. To increase cost-effectiveness and enable logical control, SDN provides high programmability and centralized view of the network through separation of network traffic delivery (the "data plane") from network configuration (the "control plane"). SDN controllers and related protocols are rapidly evolving to address the demands for scaling in complex enterprise networks. Because of the evolution of modern SDN technologies, production networks employing SDN are prone to several security vulnerabilities. The rate at which SDN frameworks are evolving continues to overtake attempts to address their security issues. According to our study, existing defense mechanisms, particularly SDN-based firewalls, face new and SDN-specific challenges in successfully enforcing security policies in the underlying network. In this paper, we identify problems associated with SDN-based firewalls, such as ambiguous flow path calculations and poor scalability in large networks. We survey existing SDN-based firewall designs and their shortcomings in protecting a dynamically scaling network like a data center. We extend our study by evaluating one such SDN-specific security solution called FlowGuard, and identifying new attack vectors and vulnerabilities. We also present corresponding threat detection techniques and respective mitigation strategies.