Topic: Computing (Page 18)

You are looking at all articles with the topic "Computing". We found 481 matches.

Hint: To view all topics, click here. Too see the most popular topics, click here instead.

πŸ”— Post-quantum cryptography: just in case

πŸ”— Computing πŸ”— Computing/Software πŸ”— Computing/Computer science πŸ”— Cryptography πŸ”— Cryptography/Computer science πŸ”— Computing/Computer Security

Post-quantum cryptography (sometimes referred to as quantum-proof, quantum-safe or quantum-resistant) refers to cryptographic algorithms (usually public-key algorithms) that are thought to be secure against an attack by a quantum computer. As of 2019, this is not true for the most popular public-key algorithms, which can be efficiently broken by a sufficiently strong quantum computer. The problem with currently popular algorithms is that their security relies on one of three hard mathematical problems: the integer factorization problem, the discrete logarithm problem or the elliptic-curve discrete logarithm problem. All of these problems can be easily solved on a sufficiently powerful quantum computer running Shor's algorithm. Even though current, publicly known, experimental quantum computers lack processing power to break any real cryptographic algorithm, many cryptographers are designing new algorithms to prepare for a time when quantum computing becomes a threat. This work has gained greater attention from academics and industry through the PQCrypto conference series since 2006 and more recently by several workshops on Quantum Safe Cryptography hosted by the European Telecommunications Standards Institute (ETSI) and the Institute for Quantum Computing.

In contrast to the threat quantum computing poses to current public-key algorithms, most current symmetric cryptographic algorithms and hash functions are considered to be relatively secure against attacks by quantum computers. While the quantum Grover's algorithm does speed up attacks against symmetric ciphers, doubling the key size can effectively block these attacks. Thus post-quantum symmetric cryptography does not need to differ significantly from current symmetric cryptography. See section on symmetric-key approach below.

Discussed on

πŸ”— Machine Identification Code

πŸ”— Computing

A Machine Identification Code (MIC), also known as printer steganography, yellow dots, tracking dots or secret dots, is a digital watermark which certain color laser printers and copiers leave on every single printed page, allowing identification of the device with which a document was printed and giving clues to the originator. Developed by Xerox and Canon in the mid-1980s, its existence became public only in 2004. In 2018, scientists developed privacy software to anonymize prints in order to support whistleblowers publishing their work.

Discussed on

πŸ”— Mode X

πŸ”— Computing

Mode X is an alternative graphics display mode of the IBM VGA graphics hardware that was popularized by Michael Abrash. It was first published in July 1991 in Dr. Dobb's Journal, and republished in chapters 47-49 of Abrash's Graphics Programming Black Book (now freely available online). The term "Mode X" was coined by Abrash.

The primary advantage of Mode X is that it has square pixels: a resolution of 320Γ—240 instead of the standard VGA Mode 13h which is 320Γ—200. Additionally, Abrash enabled the VGA's planar memory mode (also called "unchained mode"). Even though planar memory mode is a documented part of the VGA standard and was used in earlier commercial games, it was first widely publicized in the Mode X articles, leading many programmers to consider Mode X and planar memory synonymous. It is possible to enable planar memory in standard 320x200 mode, which became known as Mode Y in the Usenet rec.games.programmer group.

Planar memory arrangement splits the pixels horizontally into groups of four. For any given byte in PC video memory, four pixels on screen can be accessed depending on which plane(s) are enabled. This is more complicated for the programmer, but the advantages gained by this arrangementβ€”primarily the ability to use all 256 KB of VGA memory for one or more display buffers, instead of only one quarter of that (64 KB)β€”were considered worthwhile by many.

Discussed on

πŸ”— Expect – automates programs that expose a text terminal interface

πŸ”— Computing πŸ”— Computing/Software πŸ”— Computing/Free and open-source software

Expect is an extension to the TCL scripting language written by Don Libes. The program automates interactions with programs that expose a text terminal interface. Expect, originally written in 1990 for the Unix platform, has since become available for Microsoft Windows and other systems.

Discussed on

πŸ”— GObject

πŸ”— Computing πŸ”— Computing/Software πŸ”— Computing/Free and open-source software πŸ”— C/C++ πŸ”— C/C++/C

The GLib Object System, or GObject, is a free software library providing a portable object system and transparent cross-language interoperability. GObject is designed for use both directly in C programs to provide object-oriented C-based APIs and through bindings to other languages to provide transparent cross-language interoperability, e.g. PyGObject.

Discussed on

πŸ”— Bomba (Cryptography)

πŸ”— Computing πŸ”— Military history πŸ”— Military history/Military science, technology, and theory πŸ”— Cryptography πŸ”— Cryptography/Computer science πŸ”— Poland πŸ”— Computing/Early computers

The bomba, or bomba kryptologiczna (Polish for "bomb" or "cryptologic bomb"), was a special-purpose machine designed around October 1938 by Polish Cipher Bureau cryptologist Marian Rejewski to break German Enigma-machine ciphers.

Discussed on

πŸ”— The Magical Number 7 plus or minus 2

πŸ”— Computing πŸ”— Psychology πŸ”— Usability

"The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information" is one of the most highly cited papers in psychology. It was published in 1956 in Psychological Review by the cognitive psychologist George A. Miller of Harvard University's Department of Psychology. It is often interpreted to argue that the number of objects an average human can hold in short-term memory is 7 Β± 2. This has occasionally been referred to as Miller's law.

Discussed on

πŸ”— Alternate Instruction Set

πŸ”— Computing

The Alternate Instruction Set (AIS) is a second 32-bit instruction set architecture found in some x86 CPUs made by VIA Technologies. On these VIA C3 processors, the second hidden processor mode is accessed by executing the x86 instruction ALTINST (0F 3F). If AIS mode has been enabled, the processor will perform a JMP EAX and begin executing AIS instructions at the address of the EAX register. Using AIS allows native access to the Centaur Technology-designed RISC core inside the processor.

Discussed on

πŸ”— Fletcher's Checksum

πŸ”— Computing

The Fletcher checksum is an algorithm for computing a position-dependent checksum devised by John G. Fletcher (1934–2012) at Lawrence Livermore Labs in the late 1970s. The objective of the Fletcher checksum was to provide error-detection properties approaching those of a cyclic redundancy check but with the lower computational effort associated with summation techniques.

Discussed on

πŸ”— Judy arrays are patented

πŸ”— Computing

In computer science, a Judy array is a data structure implementing a type of associative array with high performance and low memory usage. Unlike most other key-value stores, Judy arrays use no hashing, leverage compression on their keys (which may be integers or strings), and can efficiently represent sparse data, that is, they may have large ranges of unassigned indices without greatly increasing memory usage or processing time. They are designed to remain efficient even on structures with sizes in the peta-element range, with performance scaling on the order of O(log n). Roughly speaking, Judy arrays are highly optimized 256-ary radix trees.

Judy trees are usually faster than AVL trees, B-trees, hash tables and skip lists because they are highly optimized to maximize usage of the CPU cache. In addition, they require no tree balancing and no hashing algorithm is used.

The Judy array was invented by Douglas Baskins and named after his sister.

Discussed on