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Examines paparazzi and copyright law, regulation of the Internet, the European Union Database Directive and U.S. efforts to change database laws, Tasini v. The New York Times, freedom of information and access to public sector information, company law and e-mail messages, electronic commerce, cryptography export controls, domain names and trade marks, censorship, and limited copying. (PEN)

Demonstrates the use of technology to enhance the appreciation of applications involving abstract algebra. The symbolic manipulator Maple can perform computations required for a linear cryptosystem. One major benefit of this process is that students can encipher and decipher messages using a linear cryptosystem without becoming confused and frustrated with the many intermediate computations involved. (Author/PVD)

Presents an historical overview of Vannevar Bush's efforts to develop a machine for free-form indexing and computerized information retrieval. Descriptions of the Memex concept and two related machines--the Rapid Selector and the Comparator--are provided; and the shift in emphasis to a device for business or cryptanalytic purposes is discussed. (93 references) (LRW)

Described are activities in the study of techniques used to conceal the meanings of messages and data. Some background information and two BASIC programs that illustrate the algorithms used in a new cryptographic system called "public-key cryptography" are included. (CW)

Discusses issues related to computer security, including confidentiality, integrity, and authentication or availability; and presents a selected list of Web sites that cover the basic issues of computer security under subject headings that include ethics, privacy, kids, antivirus, policies, cryptography, operating system security, and biometrics. (LRW)

Linear ciphers, substitution ciphers, public-key cryptosystems, and trapdoor knapsacks are each discussed. (MNS)

Explores the use of computers for teaching mathematical models of transposition ciphers. Illustrates the ideas, includes activities and extensions, provides a mathematical model and includes computer programs to implement these topics. (MVL)

Discussed is an application of number theory to cryptology that can be used with secondary school students. Background on the topics is given first, followed by an explanation for use of the topic. (MNS)

Reviews four books dealing with the following topics: astronomy, computers, cryptology, and physics. (AEA)

The Public Cryptography Study Group accepted the claim made by the National Security Agency that some information in some publications concerning cryptology could be inimical to national security, and is allowing the establishment of a voluntary mechanism, on an experimental basis, for NSA to review cryptology manuscripts. (MLW)

We show the following hold, unconditionally unless otherwise stated, relative to a random oracle: — There are NP search problems solvable by quantum polynomial-time (QPT) machines but not classical probabilistic polynomial-time (PPT) machines. — There exist functions that are one-way, and even collision resistant, against classical adversaries but are easily inverted quantumly. Similar counterexamples exist for digital signatures and CPA-secure public key encryption (the latter requiring the assumption of a classically CPA-secure encryption scheme). Interestingly, the counterexample does not necessarily extend to the case of other cryptographic objects such as PRGs. — There are unconditional publicly verifiable proofs of quantumness with the minimal rounds of interaction: for uniform adversaries, the proofs are non-interactive, whereas for non-uniform adversaries the proofs are two message public coin. — Our results do not appear to contradict the Aaronson-Ambanis conjecture. Assuming this conjecture, there exist publicly verifiable certifiable randomness, again with the minimal rounds of interaction. By replacing the random oracle with a concrete cryptographic hash function such as SHA2, we obtain plausible Minicrypt instantiations of the above results. Previous analogous results all required substantial structure, either in terms of highly structured oracles and/or algebraic assumptions in Cryptomania and beyond. [ABSTRACT FROM AUTHOR]

An average-case variant of the k-SUM conjecture asserts that finding k numbers that sum to 0 in a list of r random numbers, each of the order rk, cannot be done in much less than \(r^{\lceil k/2 \rceil }\) time. However, in the dense regime of parameters, where the list contains more numbers and many solutions exist, the complexity of finding one of them can be significantly improved by Wagner's k-tree algorithm. Such algorithms for k-SUM in the dense regime have many applications, notably in cryptanalysis. In this article, assuming the average-case k-SUM conjecture, we prove that known algorithms are essentially optimal for k= 3,4,5. For k> 5, we prove the optimality of the k-tree algorithm for a limited range of parameters. We also prove similar results for k-XOR, where the sum is replaced with exclusive or. Our results are obtained by a self-reduction that, given an instance of k-SUM that has a few solutions, produces from it many instances in the dense regime. We solve each of these instances using the dense k-SUM oracle and hope that a solution to a dense instance also solves the original problem. We deal with potentially malicious oracles (that repeatedly output correlated useless solutions) by an obfuscation process that adds noise to the dense instances. Using discrete Fourier analysis, we show that the obfuscation eliminates correlations among the oracle's solutions, even though its inputs are highly correlated. [ABSTRACT FROM AUTHOR]

With the development of science and technology and the appearance of various special conditions that cause signers to be unable to sign, proxy signature is gradually becoming a hot spot in cryptography research. This paper combines proxy signature, quantum teleportation, and multi-party verification and proposes a multi-party verifiable quantum proxy signature scheme based on quantum teleportation. This scheme has the following characteristics: The authentication method based on the H a s h function can effectively solve the problem of identity identification among members; in order for the proxy signer to be able to verify the correctness of the proxy authorization, a form of proxy signature authorization that concatenates the identity information of the original signer is used. The security analysis shows that our scheme is unforgeable and undeniable and can resist intercept-resend attacks and cheating attacks. [ABSTRACT FROM AUTHOR]

The article focuses on the 1943 American military operation "Operation Vengeance," which sought to kill Japanese Admiral Isoroku Yamamoto during the Solomon Islands campaign of World War II. The author discusses how Allied codebreaking was in jeopardy because of this mission and examines several published works that reflect on or avoid the event, including "Islands of Destiny," by John Prados, "Operation Vengeance," by Dan Hampton, and "We Killed Yamamoto," by Si Sheppard.

The dual-scrambling scheme that combines position transformation and bit-plane transformation is a popular image encryption scheme. However, such schemes need more key information, and the encryption and decryption processes are complicated. In addition, the existing quantum image dual-scrambling schemes mainly deal with square images. In this paper, we propose a hybrid scrambling encryption scheme for multi-mode quantum image representation (MQIR) images based on random permutation, in which the H × W quantum image is represented in MQIR. A random number generator factor s uniquely associates one of the random permutations of integers from 1 to a positive integer, so as to hybrid scramble both the pixel position and the binarized position of each pixel value. Meanwhile, the quantum circuits and some examples of scrambling are given. Furthermore, various analyses of the performance of this scheme were conducted, including effectiveness, key space, and computational complexity. By modifying the random generation factor to construct multiple binary grayscale images, the simulated results on the IBM Quantum Cloud platform demonstrate that the proposed quantum image encryption scheme is effective. In comparison to existing quantum image dual scrambling schemes, it is both simple and effective, offering a large key space, lower computational complexity, and applicability to non-square quantum images. [ABSTRACT FROM AUTHOR]