针对工业网络高可用性的主动安全防御机理研究

随着智能化的发展，现代工业网络的可用性面临着链路泛洪攻击（LFA）、网络拥塞或故障破坏等新的威胁，可造成状态测量与估计错误和控制勿动，其自身的安全保障存在如下不足：1）复杂隐蔽LFA防御方法存在攻击目标易被获取、关键路由难被迂回、攻击源检测成本极大等瓶颈问题；2）端到端丢包重传效率低，且网络结构冗余性利用不充分，难以满足强实时性要求。为此，本项目研究针对工业网络高可用性的主动安全防御机理，包括：1）复杂隐蔽LFA高效防御机制，检测被攻击的关键路由及其主机等意图，为其创建多功能等价的随机化变体以大幅度增加多样性，使攻击前置条件难成立，提升防御效果；2）弹性鲁棒通信协议，构建涵盖网络节点间多冗余子路径的可靠性最优交叠路由，满足端到端通信延迟要求，并利用工业数据流式特性，实现逐跳快速检测丢包，以及多子路径的短时高效重传，最大化端到端所容许的丢包率。上述工作将极大提升工业网络可用性的安全保障能力。

With intelligence development, the availability of the modern industrial networks faces a set of new security threats including link flooding attacks (LFAs), as well as network congestion or failures and disruptions that can lead to state measurement and estimation errors as well as wrong controls. The security assurance of the networks themselves has following deficiencies: (i) There are some bottleneck issues in the defense methods for the complicated and stealthy LFAs including the easiness in acquisition of the attacking objectives, the harness in detouring for critical routes, as well as the high cost in detection of the attacking sources. (ii) The end-to-end retransmissions for lost packets are at low efficiency, and the exploitation in the network structural redundancy is insufficient, which are hard to meet the rigid real timeliness demand in the communication. To this end, the project researches on the proactive security defense mechanism for the high availability of industrial networks that includes following content: (a) The efficient proactive defense mechanism for the complicated and stealthy LFA firstly detects the attacking intentions including the persistent routes and their hosts. Then, it creates the multiple functional equivalent randomized variants for them to significantly increase their diversity. Thus, the attacking precondition is hard to be established, which improves the defense effectiveness. (b) The resilient and robust communication protocol constructs the non-disjoint routes in optimal reliability that involve the multiple redundant sub-paths between network nodes. Further, the routes meet the rigid real-time communication demand. In addition, by exploiting the streaming features in the measurement data, the protocol achieves the lost packet detection in a hop-by-hop manner, as well as the efficient retransmission control in a short time, which maximizes the tolerable loss rate in the end-to-end communication. The above work will significantly improve the security assurance capability for the availability of the industrial networks.