由於資料通訊快速的發展，人們開始尋求快速的網路傳輸，而光纖網路具備優秀的頻寬，變成為骨幹網路的最近選擇。同時因為網路成功的融入我們生活之中，人們也開始關注網路安全的重要性，因此OCDMA同時具備彈性的架構且隱密性的系統成為許多學者研究的目標。
儘管對於其他光通訊系統來說，OCDMA具備較好的隱密性但是仍然無法完全的抵禦竊聽者，因此有作者提出許多架構來提升OCDMA的安全性,例如：使用改變使用者指配碼的動態變異碼裝置或是使用2維的動態變異碼裝置,這兩個裝置都擁有在實體層上增加安全性的能力,但是這兩個系統都沒有準確的安全機制。在現代密碼學中提出一個安全裝置必須具備加密機制以及解密所需的密鑰，目前光通訊當中很少提及安全機制以及密鑰的觀念,因此本篇提出一個安全機制利用TENT映射至M-sequence的架構。
本篇論文所提出利用TENT映射至M-sequence的架構，在傳送端可以利用TENT映射來產生序列並將這個生成序列映射到暫存器狀態,而暫存器會控制一個開關矩陣來產生動態變異碼的效果，在這個安全機制中會將密鑰經由私密通道送至接受端,接收端則利用密鑰同樣地產生暫存器狀態並控制開關矩陣來還原變異碼。本研究的架構可以大幅提升原先系統的完整性，除此之外，使用這樣的架構竊聽者在不知道密鑰的情況下無法正確的破解資訊。
本篇論文將會分兩個部分分析，分別為：第一部分對TENT映射進行敏感性的分析,以及在本篇中有個避免前後狀態重複的添加條件,還有使用NIST對我們所產生的系列進行分析第二針對竊聽者所利用的方式進行分析。最後本篇提出一個利用TENT映射至M-sequence來提升網路的安全。

In recent year, due to the information transmission rapid development, high data rate becomes people desire. However, optical communication has high bandwidth is the backbone network best choice. Since, the network is fused to the daily life, the security of network become more and more important. Therefore, OCDMA has high flexible network and confidential is the research study target.
Compared with other scheme, OCDMA has better confidentiality, but still can't avoid eavesdropper to crack data. Consequently, there are many authors proposed enhance security of OCDMA, such as, using reconfigurable mechanism to change user’s signature code or using reconfigurable mechanism over 2D code scheme, etc.. These schemes have ability to increase security on the physical layer, but they did not mention in detail the security mechanisms. In modern cryptology, a security device must have the security mechanisms and decryption keys, but the current optical communication is rarely mentioned among the security mechanisms and decryption keys. Therefore, this thesis we presented a security mechanism by using Tent/M-sequence mapping scheme.
In this thesis, we proposed a Tent/M-sequence mapping scheme to reconfigure of signature address codes. In the transmitter side, the Tent/M-sequence mapping scheme will generated the register states to control the switch matrix, and that will reconfigured signature address. Note that, the decryption keys will be transmitted through private channels. In the receiver side, by using the key as same as transmitter, it will be generated the same state to recover the reconfiguration of signature address codes. In this proposed scheme, it is enhance the integrity of security devices compared to previous scheme. In addition, by using this secure mechanism eavesdropper can’t easy detection information correctly without the decryption keys.
In this study, we will analyze the performance of two parts. Firstly, we observed the sensitivity of Tent/M-sequence mapping scheme and the repetition of states times. In addition, we will use NIST to test our chaos sequence. Secondly, we compare the schemes to reconfigurable mechanism and without reconfigurable mechanism, and also analyzing the eavesdropper adopt linear prediction to crack the data.

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