The security in MANET has become a significant and active topic within the research community. In spite of the several attacks aimed at specific nodes in MANET that have been uncovered, some attacks involving multiple nodes still receive little attention. Furthermore, it may also have to do with the fact that no survey or taxonomy has been done to clarify the characteristics of different multiple node attacks. This thesis addresses the aforementioned gap by providing a proper definition and categorization of collaborative attacks against MANET from the various multiple node attacks...