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11 
Robust computer securityAnderson, Ross John January 1994 (has links)
No description available.

12 
Analysis of some modern symmetric ciphersMirza, Fauzan ulHaque January 2002 (has links)
No description available.

13 
Uncloneable Quantum Encryption via Random OraclesLord, Sébastien 27 February 2019 (has links)
One of the key distinctions between classical and quantum information is given by the nocloning theorem: unlike bits, arbitrary qubits cannot be perfectly copied. This fact has been the inspiration for many quantum cryptographic protocols.
In this thesis, we introduce a new cryptographic functionality called uncloneable encryption. This functionality allows the encryption of a classical message such that two collaborating but noncommunicating adversaries may not both simultaneously recover the message, even when the encryption key is revealed.
We achieve this functionality by using Wiesner’s conjugate coding scheme to encrypt the message. We show that the adversaries cannot both obtain all the necessary information for the correct decryption with high probability. Quantumsecure pseudorandom functions, modelled as random oracles, are then used to ensure that any partial information that the adversaries obtain does not give them an advantage in recovering the message.

14 
Multidimensional Quantum Key Distribution with Single Side Pulse and Single Side Band Modulation MultiplexingGuerreauLambert, Olivier L. 22 November 2005 (has links)
Quantum Cryptography enables secret distribution between remotes parties where classical communications fail. The proposed technique uses optical signal modulation to encode information with relative phase difference between frequency separated signals. The single side band detection scheme (SSB) enables efficient secret key distribution. The system security is guaranteed with a strong reference protocol. One can use a fainted laser source without security breach for any distance. A second proposed technique uses relative phase difference between time separated pulses. The single side pulse detection scheme (SSP) enables efficient secret key distribution and benefits the same security features as the SSB system. Both SSP and SSB may be multiplexed to increase the secure bit rate. The maximizing initial average energy is then one photon per pulse. The implemented SSB protocol includes an autocompensation system for the optical path fluctuations that make the system robust over long time periods.

15 
Systematic cryptographic designHershey, J. E. (John E.) January 1968 (has links)
No description available.

16 
Several constructions of authentication codes with secrecy /Tian, Xiaojian. January 2004 (has links)
Thesis (Ph. D.)Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 8491). Also available in electronic version. Access restricted to campus users.

17 
Quantum Private BroadcastingSchuknecht, Christine 29 September 2021 (has links)
In Private Broadcasting, a single plaintext is broadcast to multiple recipients in an encrypted form, such that each recipient can decrypt locally. When the message is classical, a straightforward solution is to encrypt the plaintext with a single key shared among the parties, and to send each recipient a copy of the ciphertext. Surprisingly, the analogous method is insufficient in the case where the message is quantum (i.e. in Quantum Private Broadcasting (QPB)). In this work, we give three solutions to trecipient QPB and compare them in terms of encryption key length. We examine independent encryption with the quantum onetime pad, unitary tdesigns, and a new concept we define as symmetric unitary tdesigns. Of these three, symmetric tdesigns are the best choice when t is large, and these symmetric designs may be of independent interest beyond QPB.

18 
The Theory and Applications of Homomorphic CryptographyHenry, Kevin January 2008 (has links)
Homomorphic cryptography provides a third party with the ability to perform simple computations on encrypted data without revealing any information about the data itself. Typically, a third party can calculate one of the encrypted sum or the encrypted product of two encrypted messages. This is possible due to the fact that the encryption function is a group homomorphism, and thus preserves group operations. This makes homomorphic cryptosystems useful in a wide variety of privacy preserving protocols.
A comprehensive survey of known homomorphic cryptosystems is provided, including formal definitions, security assumptions, and outlines of security proofs for each cryptosystem presented. Threshold variants of several homomorphic cryptosystems are also considered, with the first construction of a threshold BonehGohNissim cryptosystem given, along with a complete proof of security under the threshold semantic security game of Fouque, Poupard, and Stern. This approach is based on Shoup's approach to threshold RSA signatures, which has been previously applied to the Paillier and Damg\aa rdJurik cryptosystems. The question of whether or not this approach is suitable for other homomorphic cryptosystems is investigated, with results suggesting that a different approach is required when decryption requires a reduction modulo a secret value.
The wide variety of protocols utilizing homomorphic cryptography makes it difficult to provide a comprehensive survey, and while an overview of applications is given, it is limited in scope and intended to provide an introduction to the various ways in which homomorphic cryptography is used beyond simple addition or multiplication of encrypted messages. In the case of strong conditional oblivious tranfser, a new protocol implementing the greater than predicate is presented, utilizing some special properties of the BonehGohNissim cryptosystem to achieve security against a malicious receiver.

19 
The Theory and Applications of Homomorphic CryptographyHenry, Kevin January 2008 (has links)
Homomorphic cryptography provides a third party with the ability to perform simple computations on encrypted data without revealing any information about the data itself. Typically, a third party can calculate one of the encrypted sum or the encrypted product of two encrypted messages. This is possible due to the fact that the encryption function is a group homomorphism, and thus preserves group operations. This makes homomorphic cryptosystems useful in a wide variety of privacy preserving protocols.
A comprehensive survey of known homomorphic cryptosystems is provided, including formal definitions, security assumptions, and outlines of security proofs for each cryptosystem presented. Threshold variants of several homomorphic cryptosystems are also considered, with the first construction of a threshold BonehGohNissim cryptosystem given, along with a complete proof of security under the threshold semantic security game of Fouque, Poupard, and Stern. This approach is based on Shoup's approach to threshold RSA signatures, which has been previously applied to the Paillier and Damg\aa rdJurik cryptosystems. The question of whether or not this approach is suitable for other homomorphic cryptosystems is investigated, with results suggesting that a different approach is required when decryption requires a reduction modulo a secret value.
The wide variety of protocols utilizing homomorphic cryptography makes it difficult to provide a comprehensive survey, and while an overview of applications is given, it is limited in scope and intended to provide an introduction to the various ways in which homomorphic cryptography is used beyond simple addition or multiplication of encrypted messages. In the case of strong conditional oblivious tranfser, a new protocol implementing the greater than predicate is presented, utilizing some special properties of the BonehGohNissim cryptosystem to achieve security against a malicious receiver.

20 
Grey Level Visual Cryptography for General Access StructuresMacPherson, Lesley January 2002 (has links)
Visual cryptography, first introduced by Naor and Shamir, allows a secret (black and white) image to be encoded and distributed to a set of participants such that certain predefined sets of participants may reconstruct the image without any computation. In 2000, Blundo, De Santis, and Naor introduced a model for greylevel visual cryptography which is a generalization of visual cryptography for general access structures. Greylevel visual cryptography extends this model to include greyscale images. Decoding is done by the human visual system. In this thesis we survey known results of greylevel visual cryptography and visual cryptography for general access structures. We extend several visual cryptography constructions to greylevel visual cryptography, and derive new results on the minimum possible pixel expansion for all possible access structures on at most four participants.

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