Topic: Computing (Page 36)
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.
π Compute Express Link
Compute Express Link (CXL) is an open standard for high-speed central processing unit (CPU)-to-device and CPU-to-memory connections, designed for high performance data center computers. CXL is built on the PCI Express (PCIe) physical and electrical interface and includes PCIe-based block input/output protocol (CXL.io) and new cache-coherent protocols for accessing system memory (CXL.cache) and device memory (CXL.mem).
Discussed on
- "Compute Express Link" | 2022-07-20 | 25 Upvotes 4 Comments
π Fifth-Generation Warfare
Fifth-generation warfare (5GW) is warfare that is conducted primarily through non-kinetic military action, such as social engineering, misinformation, cyberattacks, along with emerging technologies such as artificial intelligence and fully autonomous systems. Fifth generation warfare has been described by Daniel Abbot as a war of "information and perception". There is no widely agreed upon definition of fifth-generation warfare, and it has been rejected by some scholars, including William S. Lind, who was one of the original theorists of fourth-generation warfare.
Discussed on
- "Fifth-Generation Warfare" | 2023-11-08 | 26 Upvotes 3 Comments
π Cyrix 6x86
The Cyrix 6x86 is a line of sixth-generation, 32-bit x86 microprocessors designed and released by Cyrix in 1995. Cyrix, being a fabless company, had the chips manufactured by IBM and SGS-Thomson. The 6x86 was made as a direct competitor to Intel's Pentium microprocessor line, and was pin compatible. During the 6x86's development, the majority of applications (office software as well as games) performed almost entirely integer operations. The designers foresaw that future applications would most likely maintain this instruction focus. So, to optimize the chip's performance for what they believed to be the most likely application of the CPU, the integer execution resources received most of the transistor budget. This would later prove to be a strategic mistake, as the popularity of the P5 Pentium caused many software developers to hand-optimize code in assembly language, to take advantage of the P5 Pentium's tightly pipelined and lower latency FPU. For example, the highly anticipated first-person shooter Quake used highly optimized assembly code designed almost entirely around the P5 Pentium's FPU. As a result, the P5 Pentium significantly outperformed other CPUs in the game.
Discussed on
- "Cyrix 6x86" | 2024-10-30 | 24 Upvotes 5 Comments
π Dancing Links (A very useful hack by Knuth)
In computer science, dancing links is a technique for reverting the operation of deleting a node from a circular doubly linked list. It is particularly useful for efficiently implementing backtracking algorithms, such as Donald Knuth's Algorithm X for the exact cover problem. Algorithm X is a recursive, nondeterministic, depth-first, backtracking algorithm that finds all solutions to the exact cover problem. Some of the better-known exact cover problems include tiling, the n queens problem, and Sudoku.
The name dancing links, which was suggested by Donald Knuth, stems from the way the algorithm works, as iterations of the algorithm cause the links to "dance" with partner links so as to resemble an "exquisitely choreographed dance." Knuth credits Hiroshi Hitotsumatsu and KΕhei Noshita with having invented the idea in 1979, but it is his paper which has popularized it.
Discussed on
- "Dancing Links (A very useful hack by Knuth)" | 2010-06-01 | 21 Upvotes 7 Comments
π Unreal Mode
In x86 computing, unreal mode, also big real mode, huge real mode, flat real mode, or voodoo mode is a variant of real mode, in which one or more segment descriptors has been loaded with non-standard values, like 32-bit limits allowing access to the entire memory. Contrary to its name, it is not a separate addressing mode that the x86 processors can operate in. It is used in the 80286 and later x86 processors.
Discussed on
- "Unreal Mode" | 2019-03-18 | 27 Upvotes 1 Comments
π Domain Fronting
Domain fronting is a technique for Internet censorship circumvention that uses different domain names in different communication layers of an HTTPS connection to discreetly connect to a different target domain than is discernable to third parties monitoring the requests and connections.
Due to quirks in security certificates, the redirect systems of the content delivery networks (CDNs) used as 'domain fronts', and the protection provided by HTTPS, censors are typically unable to differentiate circumvention ("domain-fronted") traffic from overt non-fronted traffic for any given domain name. As such they are forced to either allow all traffic to the domain frontβincluding circumvention trafficβor block the domain front entirely, which may result in expensive collateral damage and has been likened to "blocking the rest of the Internet".
Domain fronting does not conform to HTTP standards that require the SNI extension and HTTP Host header to contain the same domain. Many large cloud service providers, including Amazon, Microsoft, and Google, actively prohibit domain fronting, which has limited it as a censorship bypass technique. Pressure from censors in Russia and China is thought to have contributed to these prohibitions, but domain fronting can also be used maliciously.
A newer variant of domain fronting, domain hiding, passes an encrypted request for one resource (say, a website), concealed behind an unencrypted (plaintext) request for another resource whose DNS records are stored in the same cloud. It has much the same effect. Refraction networking is an application of the broader principle.
π Lace Card
A lace card is a punched card with all holes punched (also called a whoopee card, ventilator card, flyswatter card, or IBM doily). They were mainly used as practical jokes to cause disruption in card readers. Card readers tended to jam when a lace card was inserted, as the resulting card had too little structural strength to avoid buckling inside the mechanism. Card punches could also jam trying to produce cards with all holes punched, owing to power-supply problems. When a lace card was fed through the reader, a card knife or card saw (a flat tool used with punched card readers and card punches) was needed to clear the jam.
Discussed on
- "Lace Card" | 2023-06-23 | 23 Upvotes 5 Comments
π 2024 CrowdStrike incident: The largest IT outage in history
On 19 July 2024, a faulty update to security software produced by CrowdStrike, an American cybersecurity company, caused innumerable computers and virtual machines running Microsoft Windows to crash. Businesses and governments around the globe were affected by what one expert called the "largest IT outage in history".
Among the industries that were disrupted were airlines, airports, banks, hotels, hospitals, stock markets, and broadcasting; governmental services such as emergency numbers and websites were also affected. The error was discovered and a fix was made on the same day, but the outage continued to delay airline flights, cause problems in processing electronic payments, and disrupt emergency services.
Discussed on
- "2024 CrowdStrike incident: The largest IT outage in history" | 2024-07-19 | 24 Upvotes 4 Comments
π Nagle's Algorithm
Nagle's algorithm is a means of improving the efficiency of TCP/IP networks by reducing the number of packets that need to be sent over the network. It was defined by John Nagle while working for Ford Aerospace. It was published in 1984 as a Request for Comments (RFC) with title Congestion Control in IP/TCP Internetworks in RFCΒ 896.
The RFC describes what he called the "small-packet problem", where an application repeatedly emits data in small chunks, frequently only 1 byte in size. Since TCP packets have a 40-byte header (20 bytes for TCP, 20 bytes for IPv4), this results in a 41-byte packet for 1 byte of useful information, a huge overhead. This situation often occurs in Telnet sessions, where most keypresses generate a single byte of data that is transmitted immediately. Worse, over slow links, many such packets can be in transit at the same time, potentially leading to congestion collapse.
Nagle's algorithm works by combining a number of small outgoing messages and sending them all at once. Specifically, as long as there is a sent packet for which the sender has received no acknowledgment, the sender should keep buffering its output until it has a full packet's worth of output, thus allowing output to be sent all at once.
Discussed on
- "Nagle's Algorithm" | 2022-12-30 | 25 Upvotes 2 Comments
π DNA Computing
DNA computing is a branch of computing which uses DNA, biochemistry, and molecular biology hardware, instead of the traditional silicon-based computer technologies. Research and development in this area concerns theory, experiments, and applications of DNA computing. The term "molectronics" has sometimes been used, but this term has already been used for an earlier technology, a then-unsuccessful rival of the first integrated circuits; this term has also been used more generally, for molecular-scale electronic technology.
Discussed on
- "DNA Computing" | 2018-12-16 | 11 Upvotes 15 Comments