在信息技術蓬勃發展之下，個人資訊的數位化已成現代人日常生活的一部分，但在便攜式數據儲存設備、網際網路與雲端服務普及之下，資訊安全儼然成為一個重要的議題，其中數據加密更是一個蓬勃發展的項目。
本文對於硬體通訊上的安全性，提供了一個基於四維度渾沌系統的並列埠傳輸技術，首先透過二維相圖、對稱性分析、平衡點分析、散度分析與Lyapunov指數圖，分析本文提出的新四維度渾沌系統，模擬並確認其渾沌特性可透過尤拉法則產生渾沌序列，作後續加密處理之用。
在密碼學中，混淆(confusion)與擴散(diffusion)是設計加密演算法的主要方法；在本實驗中，首先透過渾沌系統產生的亂數序列，對原始數據進行位元級的排列置換，為混淆階段的方法，接著再以渾沌系統產生的亂數對數據作取代置換，為擴散階段的方法。該密碼系統實現於Altera DE2-115 FPGA的開發板上，是一支持並列埠傳輸的渾沌加密處理器。
為了針對上述加密演算法作安全性分析，實驗中以BMP彩色圖片作為原始數據，經由加密處理後儲存至SD卡中，再以Matlab作圖片加密效果分析，最終可從實驗中驗證透過此新四維度的渾沌加密方法，是一個設計簡單且效果良好的加密處理器。

With the rapid development of information technology, portable data storage devices, Internet and cloud services have become a part of human daily life. For the digitization of personal information, information security has become a significant issue, in which data encryption is one of the popular research object.
In this study, a parallel port transmission technique based on four-dimensional chaotic system is proposed for the security of hardware communication. Applying the Matlab to analyze the new 4D chaotic system’s properties which include 2D phase portraits, symmetry and invariance, divergence analysis, equilibrium analysis and Lyapunov exponent diagrams.
First, through the two-dimensional phase portraits, divergence analysis, equilibrium analysis and Lyapunov exponent diagram, the new four-dimensional chaotic system is simulated and confirmed that its chaotic properties can be used to generate chaotic sequences through the Euler’s method as the shuffle sequence.
In cryptography, confusion and diffusion operations are the main methods for designing the encryption algorithm. In this experiment, all the encryption operation is performed by generating chaotic sequence. In the confusion phase, the characteristic of chaotic pseudorandom sequence is used to shuffle the data content by bit-level permutation. Next, the pixel characters are also substituted by using chaotic pseudorandom number in diffusion phase. All the function for cryptosystem is implemented by Altera DE2-115 FPGA which supports the chaotic secure on parallel transmission.
In order to analyze the security of proposed encryption algorithm, a BMP color image will be encrypted and accessed through FPGA. Finally, result of the Matlab analysis, we can get the conclusion of the new 4D chaotic system is a high security and simple-design for a cryptosystem.

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