SADI: A Novel Model to Study the Propagation of Social Worms ,As more and more people rely on social networks for business and life, social worms constitute one of the major security threats to our society. Modern social worms exhibit two new features, message notification and the temporal characteristic of human mobility . Message notification indicates a user will get a reminder once a new message comes to a social account. The temporal characteristic of human mobility indicates a user can operate corresponding computer in different locations with different resting time. Previous scholars have proposed some analytical models for the propagation dynamics of social worms. However, they did not consider the above two features and there is one critical problem unrealized, which is structural imperfection of network topology . Previous models have not taken into account the hierarchical topology structure, which results from a many-to-many relationship between users and hosts. To address these problems, we model propagation dynamics of social worms oriented hierarchical networks in this paper, and the proposed model accurately describes the propagation behavior of social worms. We conduct both a theoretical analyses and extensive simulations to show our model can overcome inaccuracy in the number of infected nodes and provide a stronger approximation for the worm propagation. The results show that our model presented in this paper achieves a greater accuracy in characterizing the propagation of modern social worms.

 

The topologies of social worms consist of a social logical layer and an actual physical layer. The
former has following characteristics:
• They are defined as a ”semi-directed network”, in which some edges are directed and
others are undirected.
• The indegree of nodes tends to match the out degree, and they both follow the power law
distribution.
• they are assortative, which implies that nodes with a high degree tend to connect with
each other.
• The weight of each edge denotes the propagation probability from user i to user j.
• Each node in the social logical layer contains a group of nodes corresponding to nodes inthe actual physical layer.

 

• they are defined as a ”semi-directed network”, in which some edges are directed and
others are undirected.
• one critical problem in this models is message notification.

 

 

We propose a novel SADI model for the propagation of social worms. This model is able to address two core processes and one critical problem in previous models: message notification, the temporal characteristic of human mobility and structural imperfection of network topology. We then conducted a number of experiments to analyze how these factors impact on the spread of worms. Moreover, the experiments show that our SADI model fits the simulation very well, which implies the accuracy for modeling the propagation dynamics is very good. Finally, we also believe our work presented in this paper is of great significance to network defense.

 

• SADI model is more accurate than the state-of-threat models.
• Its advantage is reminding the user to check new messages in time