在現今的研究成果下，量子運算技術已經被證明會威脅當下使用的非對稱金鑰加密系統(如：RSA)。換言之，由於量子電腦強大的平行運算能力，許多基於複雜數學難題的加密系統將會被量子電腦以多項式時間內所破解[1]，因此在近幾年量子密碼的研究受到許多的重視與關注，亦有許多應用被提出。
在量子密碼的研究開始發展後，量子網路的概念亦呼之欲出。網路的基本訴求是為了讓兩個或以上的使用者能夠互相通訊，因為使用者之間的距離過長以至於無法直接做溝通，所以使用者們需藉由中繼點或路由的協助下傳送訊息給對方。然而在量子網路中，如何在使用者之間分享量子糾結態是個重要的議題，由於量子長距離的傳輸會造成能量的消耗，最後造成量子態的改變或是消失。此外量子暴露在網路傳輸下，使得量子有機會被竊聽者攔截而得到資訊，或是有機會對網路做中間人攻擊。
另外在資訊安全領域中，匿名亦為一重大的討論議題，不同於一般關注在資料安全的研究，匿名著重於如何隱藏訊息的傳送者或接收者的身分，像是可以應用於投票、拍賣或電子郵件等等。在近幾年，洋蔥路由(Tor)成為最知名的匿名網路系統[2]，藉由洋蔥路由的幫助，可以供使用者或是服務提供者匿名的功能。除此之外其洋蔥加密的特性，可讓在網路中傳送的訊息無法被追蹤，以避免他人追蹤訊息的路徑來尋找訊息的發送者。
在本論文中，將提出基於不誠實中繼之分散式量子網路，用以讓長距離的使用者間安全的分享量子糾結態，並免於被竊聽者實施中間人攻擊的可能。此外亦提出兩個量子匿名通訊的環境(量子洋蔥路由與量子隱匿服務)，同時結合量子密碼的優點與洋蔥路由的特性，在量子洋蔥路由(QOR)中，相較於傳統的洋蔥路由需要分別與路由一步一步地分享金鑰，在提出的量子洋蔥路由中，傳送者可以同時與傳遞路徑上的路由們同時分享金鑰，亦可匿名地傳送訊息並且保護的安全性，在量子隱匿服務(QHS)的環境下，基於量子洋蔥路由的特點，訊息傳送者與服務提供者同時皆可匿名，並且訊息的安全性亦可得到保護。

Nowadays, the quantum computation, which is based on quantum mechanics, has been proven to be a serious threat against the security of the well-used public key cryptosystem (e.g. RSA). Precisely, the quantum computer has the ability of the powerful parallel process, where this feature causes the cryptosystems which are based on the difficulty of mathematic problems being cracked in polynomial time [1]. That inspires more research of the quantum cryptography to resolve the issue with several proposed applications, such as quantum key distribution (QKD), quantum secure direct communication (QSDC), and quantum secret sharing (QSS), and therefore the property of the quantum cryptography gradually attracts more focus in the field of the information security.
Furthermore, the concept of the quantum network has been provided. The purpose of the network is to communicate between the distant participants, where the participants need to send the message with the help from relays or routers because the distance makes them unable to transmit directly. In the quantum network, especially, distributing the entangled state between the distant participants is one of the core issues since the distance causes the quantum energy decreasing, and additionally it may give an eavesdropper and the untrusted relay the opportunity to operate Man-in-the-Middle attack or obtain any useful information during the transmission.
In addition, the anonymity is also a significant issue for information security. Apart from protecting the privacy of the message, the anonymity tends to hide the identity of the sender or the receiver. In that case, the feature of anonymity can be implemented in some applications in the classical cryptography, which require the anonymity, like voting, sending email, auction, and so on. Recently, the onion routing (Tor) [2] becomes the well-known protocol which provides the anonymity for the initiator (sender) and the service provider with the help of several onion routers. Besides, because of the onion encryption/decryption method, the transmitted message is untraceable preventing from others to track the path to find the initiator.
Based on the above discussion, this thesis presents a distributed quantum network (DQN) with the untrusted relays in order to safely share the entanglement between each participant in long distance without the threat from Man-in-the-Middle attack. Moreover, two quantum anonymous environments, called quantum onion routing (QOR) and quantum hidden service (QHS) are also presented, which include the advantages of the quantum cryptography and the features of the onion routing. In the first anonymous environment, unlike the conventional onion routing an initiator can simultaneously share keys among the multiple routers with an efficient way, and then anonymously sends the message to a public service provider. On the other hand, the second one allows both initiator and the service provider to be anonymous.

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