Optical Fiber Transmission And FPGA Implementation Of Digital Chaos Encryption

The information carrier is no longer limited to text content companying with the upgrading of digital technology,and the digital transmission business of multimedia data such as voice,image and video is in the ascendant.At the same time,the progress of optical fiber communication technology has also tremendously increased the capacity of the transmission channel,which providing an effective route to transmit mass multimedia information.In consequence,whether it is video chats,webcasts,or aeronautic communications,digital video signals can carry added as well as convey more important information intuitively along with the world has begun to enter the era of streaming media.However,the transmission of message is always accompanied by information security issues,especially for those industries that require relatively high security,which entails it is essential to ensure the confidentiality of its communication.Therefore,secure communication technology is a significant aspect of information technology elaboration,meanwhile,chaotic secure communication is a rising development orientation of secure communication technology.The chaotic and divergent characteristics of chaos coincide with the confusion and diffusion features in the traditional encryption system.And it conforms to the encryption method of One-Time Pad via relating quasi-random sequences generated by chaotic system iterations with streaming data.Moreover,the chaotic system is sensitive to the initial,and the slight change of the key parameters will cause the avalanche effect of the ciphertext,which provides sufficient security for the encryption system.Hence,on the basis of the appeal,taking the digital high-definition video stream data as the processing object,and fibre channel as the transmission medium,this thesis designs a chaotic stream cipher algorithm suitable for video processing,and gives the implementation method by Field Programmable Gate Array(FPGA).The main contents of thesis are as follows:1.According to the chaos anti-control principle,a Three-Dimensional Self-Synchronous Chaotic Stream Cipher(3-D SCSC)algorithm which can resist the divide-and-conquer attack and chosen-ciphertext attack is designed,and gives the provement of its self-synchronization principle.Then,transforming the algorithm from real number field to integer field and completeing fixed-point,after which uses FPGA simulation to verify the correctness of the algorithm implementation and adopts pipeline technology to increase the operating frequencyuses of effectuation.2.Following the FPGA modular design method and applying Micro Blaze soft core to control,throught that it is able to build a digital chaotic encryption communication system with optical fiber and establishs the real-time video encryption and decryption data stream between sender and receiver,data flow of video cache and display together with the data flow path of GTP-SFP.Besides,provides a program solidification method for small data volume operations bases on Micro Blaze.3.Tests the hardware implementation results of the system to verify the encryption consequents and observes the resource consumption of the system.In addition,the NIST test is carried out on the iterative sequence of the 3-D SCSC algorithm,and then trials run the sensitivity of the key parameters.At last,calculates in the meantime analyses the statistical characteristics and information entropy of the plaintext and ciphertext.The results show that the algorithm has a good encryption quality,and the system has a high security.