Abstract: Internet worms have drawn significant attention due to their enormous threats to the Internet. Inspired by the predator/prey model in the biology, this paper uses a mathematical model to study the interaction between worms（preys） and benign worms（predators）. A new interaction model is proposed to combat the propagation of worms. In virtue of this model, the basic reproduction number that governs whether or not a worm is extinct is obtained. The impact of different parameters of predators is studied. Simulation results show that the performance of the model is effective in combating such worms, in terms of decreasing the number of preys and reducing the prey propagation speed. Moreover, the model can propose some baselines in combating worms.

Key words: network security, interaction model, predator, basic reproduction number, equilibrium

摘要： 网络蠕虫的传播速度极快，能在很短时间内感染大量主机，对网络基础设施构成了极大的威胁。受生物动力系统研究领域中的捕食者/食饵模型的启发，利用数学模型研究了网络蠕虫（食饵）和良性蠕虫（捕食者）间的交互动态行为。为了遏制网络蠕虫的传播，提出了一种交互模型，利用此模型，得到了蠕虫灭绝与否的阈值——基本再生数，研究了捕食者相关参数对交互模型的影响。仿真结果表明，此交互模型能有效遏制蠕虫的传播，能明显减少感染主机数和降低蠕虫传播速度，为遏制蠕虫传播提供了理论指导。

关键词: 网络安全, 交互模型, 捕食者, 基本再生数, 平衡点