Coalition formation, surveillance, and network security: modeling, design, and evaluation
Mobile sensors have been widely applied in sensing applications. The performance of mobile sensors in intrusion detection has drawn a lot of attention from researchers. In this dissertation, we model the behaviors of mobile sensors in a few scenarios of applications and study their performances. In addition to the performance, the control schemes of the mobile sensors are a hot research topic, especially, when cooperation between mobile sensors is concerned. Basically, the control schemes can be global ones in which the mobile sensors are configured as a whole or distributed ones in which the moving sensors themselves have some level of autonomy of their actions. In this dissertation, two techniques, the non-game-theoretic and the game-theoretic, will be used according to global control scheme and distributed control scheme, respectively. Regarding the distributed control scheme, we will explore the potential collaboration between the mobile sensors which we view as a coalition formation game. With the incentive of a mobile sensor to maximize its payoff and the tradeoff between the higher detecting ability gained by cooperation (in the form of forming coalition) and the cost to form the coalition, the game-theoretic technique is a tool for our study in the coalition formation game. Using game theory, we show how the behaviors/strategies of the mobile sensors in the coalition formation game affect their payoffs. Computer networks have been ubiquitous, while network security issues have been always changing as more sophisticated attack techniques and strategies have been coming out. Countermeasures must be developed and applied to guarantee desired levels of security. Among those countermeasures, cryptography is widely applied in network communications to provide confidentiality, authenticity, and integrity. Without reasonable configuration, the usage of encryption and decryption could introduce loss of the performance in network transmission traffic. This dissertation studies how the performance of network transmissions in a channel using Sliding-Window flow control is affected by the configuration of the studied cypher scheme, the Cipher Feedback mode, and explores the optimal configuration of the scheme without reducing the security provided by the Cipher Feedback mode.