Exact Secrecy Throughput Capacity Study In MANETs

The Mobile Ad-hoc Network(MANET)is flexible and easy to be deployed.It is widely used in military battlefield,emergency rescue,disaster relief,etc.Now the available works focus on deriving the scaling law results of throughput capacity in MANET.It reflects how the throughput capacity of the MANET scales up as the network size tends to infinity.It is unable to provide accurate theoretical guidance for network design.At the same time,due to the open nature of wireless medium,the security of MANET is facing a great threat.According to the physical-layer(PHY)security technology,this thesis studies the exact secrecy throughput capacity(STC)in MANET.It is expected to provide theoretical guidance for the design and optimization of Wireless Ad-hoc Network(WANET)and critical to facilitate the design,development and commercialization of MANET.For the problem that the scaling law results of STC cannot characterize the exact STC results,this thesis focuses on studying the exact result of STC in a cell-partitioned MANET.First,this thesis considers the secrecy guard zone scenario.For this scenario,we assume that each legitimate transmitter can detect eavesdroppers within a certain range around it.The range is called as secrecy guard zone.According to this scenario,we propose the secrecy guard zone based secure transmission scheme.This scheme can provide perfect secure transmission for the physical layer.We derive exact analytical expression for the STC of the concerned network under the secrecy guard zone scenario,based on the analysis of secure(resp.sourcedestination)transmission probability.Different from the existing results,the exact STC not only reflects the relationship between STC and network size,but also characterizes the impact of other key parameters on the network performance.Aiming to the difficulty of calculating the STC of cooperative scenario in MANET,this thesis considers the cooperative scenario.We assume that each legitimate transmitter can know the exact location information of eavesdroppers within its transmission range.For this scenario,we propose the cooperative jamming based secure transmission scheme.In this scheme,the non-transmission legitimate nodes send artificial noise to interfere eavesdroppers within the same cell.When all the eavesdroppers in the transmission range are interfered,the transmission can be conducted.With the help of the theoretical framework for STC analysis of MANET,we derive exact analytical expression for the STC of the cooperative jamming scenario.This thesis provides simulation to validate the theoretical analysis of STC in MANET.And we also compare the secrecy guard zone based scenario with the cooperative jamming based scenario in terms of the STC.At the same time,this thesis also explores the impacts of network parameters(the number of eavesdroppers,the size of secrecy guard zone,the transmission range and so on)on the STC performance of MANET.