Design And Implementation Of Secrecy Intercom System Based On Network

With the popularity of the Internet and the upgrading of its transmission rate, it hasbecome possible to transmit voice through the network, but the openness of the Internet putforward higher challenge to the security of voice communications. Voice signals have somefeatures including large data, uneven distributed energy, high redundancy, meanwhilechaotic system can generate chaotic sequence to meet the basic features of cryptographybased on a few parameters, and chaotic sequence is predictable in the short term butunpredictable for a long time. All in all, chaotic sequence as signal encryption key is verysuitable. Although recent studies have found security problem in encryption methods basedon chaotic stream synchronizing, the system uses the chaotic sequence as the key, uses otherencryption algorithm to encrypt the voice, can effectively avoid the risk caused by chaoticstream key losing.In order to improve the security of VoIP, this paper designed and implemented a voiceencryption and decryption system based on chaotic keys with the core of TI’s DSP5509Achip. In the voice communication process, dynamic root key technology is used to generateencryption keys through Henon map, improved Logistic and nonlinear replacement, and theIDEA Algorithm is used to encrypt voice data, the receiver generates IDEA decryption keybased on dynamic root key and decrypts the cipher text.In this paper, the confidential phone system is introduced respectively from the overalldesign, research and analysis of voice encryption and decryption algorithms, the hardwareand software design, etc. The hardware design mainly includes DSP processor, itsperipherals, JTAG interface, voice processing module, data storage module, netcommunication module and bootloader module hardware design. The software designmainly includes the initialization of VC5509A, voice communication, encryption keys,encryption-decryption algorithm and bootloader. Meanwhile, the hardware design hasanti-jamming design to improve the reliability and stability of the system.After joint debugging the system hardware and software, confidential phone systemachieves the desired effect in this paper. The whole system is stable, and is able to meet therequirements of real-time voice communication, reach the voice data encryption anddecryption effects. In addition, the target board is scalably designed, and the system has acertain practical value and application prospect.Finally, the design of the entire confidential phone system process and test results are summarized, and the project follow-up work is prospected.