Abstract: The network-level moving target defense is an effective approach to deal with the cyber attacks, like flooding attack. However, the existing network-level moving target defense systems mostly adopt the static central controller. This kind of centralized management architecture is prone to risks such as single point of failure or untrusted data. To address the above problems, this paper proposes a scheme of network-level moving target defense system based on blockchain, which realizes dynamically switching the central controller through the PoW consensus mechanism and overcomes the single point of failure of it and improves its robustness. In addition, based on the distributed trusted network environment constructed by blockchain, this paper establishes load balancing mechanism and disaster-tolerant backup mechanism for the dynamic central controller, making the system have good performance in dealing with the high concurrent service requests and recovering quickly from paralysis. Finally, this paper designs and implements the prototype system of network-level moving target defense system based on blockchain. The test results show that the designed system has good availability and robustness.

Key words: moving target defense, blockchain, decentralization, load balancing, disaster-tolerant backup