| The real-time embedded system has been widely applied in many fields, such asthe industrial control and scientific research, which helps to reduce the managementcost as well as increase the efficiency. Embedded devices have improved theinformatization of whole society, but also faced more and more new challenges. Nomatter for the distributed or just single-processor system, the gradually widenedapplication will obvious lead more real-time embedded system running in theunpredictable environment. Following with the development of network technology,especially the raise of cyber-physics network, the reliance of network becomes moreserious. Hence, when designing the real-time embedded system, researchers shouldconsider its real-time performance but cannot ignore the safety requirement.Unfortunately, the weakness of processing ability and limited energy supply make thisdesign harder.Considering the features of real-time embedded system, the real-time, security andenergy saving, combine the difference between distributed and single-processor system,the major job in this thesis is try to introduce the feedback theory into the real-timeembedded system and design adaptive security management mechanism. In order tomake this research more accurate, the first job is to measure the time and energyconsumption of some popular cryptography algorithms in real embedded platform.Those measured data is not only necessary for this current research, but must helpful forother researches in this related area.No matter for the single-processor or distributed system, this thesis will deployfeedback controller to achieve the dynamic security management. In simplification,surveillance component will monitor the system runtime status, and send the result tocontrollers. The controllers can find the error between the actual and desired status, andcompute the offset. Based on this offset, actuator will finally complete the automaticcontrol. The architecture of single-processor is simple, so its design can be moreconcentrate on the framework design. However, the complicated architecture ofdistributed system makes it is necessary to consider and analyze the details of feedback controller.The proposal of this thesis, the feedback control based adaptive securitymanagement mechanism, will be verified by a series of simulations. Through thecomparison, it can be concluded that comparing with static security managementpolicies, dynamic management has obvious advantages especially when the runtimeenvironment is unpredictable. |
