一个网络安全风险评估模型的研究与设计

RESEARCH ON THE DESIGN OF NETWORK RISK ASSESSMENT MODEL

风险评估是综合的网络安全体系的基础和关键。在传统的风险评估中,大粒度的评测结果不能给管理员提供切实有用的信息。对此,提出了基于漏洞扫描和攻击效果评测的安全评估模型,采用自下而上、先局部后整体的层次化评估策略,利用服务和主机自身的重要性因子加权,分别计算服务、主机以及整个网络系统的风险指数,进而分析整个系统的安全态势。仿真试验测试表明,该模型能够准确评估服务、主机和网络系统3个层次的安全态势,在一定程度上提高了评估结果的准确性和一致性。

Risk evaluation is the foundation of network security management. In traditional risk evaluation, useful security information cannot be obtained from big granularity assessment results. To cope with the problem, a new model based on vulnerability scan and attack effect evaluation, is proposed, which adopts a hierarchical evaluation policy, called ＂bottom to top, local to global＂ , to calculate the risk exponents of service, host and network system respectively by weighting the importance of service and host. A prototype is initially implemented which can evaluate the security situation in three levels： service, host and network system. Experiments show that the system can improve accuracy and consistency of assessment in certain extent.