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Base 32
Base32 is the base-32 numeral system. It uses a set of 32 digits, each of which can be represented by 5 bits (25). One way to represent Base32 numbers in a human-readable way is by using a standard 32-character set, such as the twenty-two upper-case letters A–V and the digits 0-9. However, many other variations are used in different contexts. The rest of this article discusses the use of Base32 for representing byte strings, not unsigned integer numbers, similar to the way Base64 works. This is an example of a Base32 representation using the previously described 32-character set ( IPFS CIDv1 in Base32 upper-case encoding): Advantages Base32 has a number of advantages over Base64: # The resulting character set is all one case, which can often be beneficial when using a case-insensitive filesystem, DNS names, spoken language, or human memory. # The result can be used as a file name because it cannot possibly contain the '/' symbol, which is the Unix path separator. # The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radix
In a positional numeral system, the radix or base is the number of unique digits, including the digit zero, used to represent numbers. For example, for the decimal/denary system (the most common system in use today) the radix (base number) is ten, because it uses the ten digits from 0 through 9. In any standard positional numeral system, a number is conventionally written as with ''x'' as the string of digits and ''y'' as its base, although for base ten the subscript is usually assumed (and omitted, together with the pair of parentheses), as it is the most common way to express value. For example, (the decimal system is implied in the latter) and represents the number one hundred, while (100)2 (in the binary system with base 2) represents the number four. Etymology ''Radix'' is a Latin word for "root". ''Root'' can be considered a synonym for ''base,'' in the arithmetical sense. In numeral systems In the system with radix 13, for example, a string of digits such as 398 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2 (number)
2 (two) is a number, numeral and digit. It is the natural number following 1 and preceding 3. It is the smallest and only even prime number. Because it forms the basis of a duality, it has religious and spiritual significance in many cultures. Evolution Arabic digit The digit used in the modern Western world to represent the number 2 traces its roots back to the Indic Brahmic script, where "2" was written as two horizontal lines. The modern Chinese and Japanese languages (and Korean Hanja) still use this method. The Gupta script rotated the two lines 45 degrees, making them diagonal. The top line was sometimes also shortened and had its bottom end curve towards the center of the bottom line. In the Nagari script, the top line was written more like a curve connecting to the bottom line. In the Arabic Ghubar writing, the bottom line was completely vertical, and the digit looked like a dotless closing question mark. Restoring the bottom line to its original horizonta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrologica X1
The Electrologica X1 was a digital computer designed and manufactured in the Netherlands from 1958 to 1965. About thirty were produced and sold in the Netherlands and abroad. The X1 was designed by the Mathematical Centre in Amsterdam, an academic organization that had been involved in computer design since 1947, and manufactured by Electrologica NV, * a company formed expressly for the purpose of producing the machine. The X1 was a solid-state binary computer ("completely transistorized") with magnetic core memory. Word-length was 27 bits and peripherals included punched and magnetic tape. It was one of the first European computers to have an interrupt facility. The X1 was the subject of Edsger Dijkstra's Ph.D. dissertation, and the target of the first complete working ALGOL 60 compiler, completed by Dijkstra and Jaap Zonneveld. In 1965, the X1 was superseded by the X8. Electrologica was taken over by Philips a few years later. Instruction set The X1 allowed conditional exec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Douglas Crockford
Douglas Crockford is an American computer programmer who is involved in the development of the JavaScript language. He specified the data format JSON (JavaScript Object Notation), and has developed various JavaScript related tools such as the static code analyzer JSLint and minifier JSMin. Of his books, "JavaScript: The Good Parts" was published in 2008, followed by "How JavaScript Works" in 2018. He was a senior JavaScript architect at PayPal until 2019, and is also a writer and speaker on JavaScript, JSON, and related web technologies. Education Crockford earned a degree in Radio and Television from San Francisco State UniversityDouglas Crockford speaker biography , New Paradigms for Using Computers conference, IBM Almaden Research Center, August 22, 1996 in 1975. He took classes in < ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tahoe-LAFS
Tahoe-LAFS (Tahoe Least-Authority File Store) is a free and open, secure, decentralized, fault-tolerant, distributed data store and distributed file system. It can be used as an online backup system, or to serve as a file or Web host similar to Freenet, depending on the front-end used to insert and access files in the Tahoe system. Tahoe can also be used in a RAID-like fashion using multiple disks to make a single large Redundant Array of Inexpensive Nodes (RAIN) pool of reliable data storage. The system is designed and implemented around the "principle of least authority" (POLA), described by Brian Warner (one of the project's original founders) as the idea "that any component of the system should have as little power of authority as it needs to get its job done". Strict adherence to this convention is enabled by the use of cryptographic capabilities that provide the minimum set of privileges necessary to perform a given task by asking agents. A RAIN array acts as a storage v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ZRTP
ZRTP (composed of Z and Real-time Transport Protocol) is a cryptographic key-agreement protocol to negotiate the keys for encryption between two end points in a Voice over IP (VoIP) phone telephony call based on the Real-time Transport Protocol. It uses Diffie–Hellman key exchange and the Secure Real-time Transport Protocol (SRTP) for encryption. ZRTP was developed by Phil Zimmermann, with help from Bryce Wilcox-O'Hearn, Colin Plumb, Jon Callas and Alan Johnston and was submitted to the Internet Engineering Task Force (IETF) by Zimmermann, Callas and Johnston on March 5, 2006 and published on April 11, 2011 as . Overview ZRTP ("Z" is a reference to its inventor, Zimmermann; "RTP" stands for Real-time Transport Protocol) is described in the Internet Draft as a ''"key agreement protocol which performs Diffie–Hellman key exchange during call setup in-band in the Real-time Transport Protocol (RTP) media stream which has been established using some other signaling protocol such as S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phil Zimmermann
Philip R. Zimmermann (born 1954) is an American computer scientist and Cryptography, cryptographer. He is the creator of Pretty Good Privacy (PGP), the most widely used email encryption software in the world. He is also known for his work in VoIP encryption protocols, notably ZRTP and Zfone. Zimmermann is co-founder and Chief Scientist of the global encrypted communications firm Silent Circle (software), Silent Circle. Background He was born in Camden, New Jersey. Zimmermann received a B.S. degree in computer science from Florida Atlantic University in Boca Raton, Florida in 1978. In the 1980s, Zimmermann worked in Boulder, Colorado as a software engineer on the Nuclear Weapons Freeze Campaign as a military policy analyst. PGP In 1991, he wrote the popular Pretty Good Privacy (PGP) program, and made it available (together with its source code) through public FTP for download, the first widely available program implementing public-key cryptography. Shortly thereafter, it became a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mnet (Computer Program)
Mnet is software to run a peer-to-peer distributed data store for file sharing purpose. It aimed at substituting free sharing of digital resources, typical of P2P networks, with a market regulated by its own currency. Mnet is a fork of the software MojoNation. Evil Geniuses for a Better Tomorrow Evil Geniuses for a Better Tomorrow was a startup company founded by Jim McCoy et al. to create MojoNation. The company's name comes from the game Illuminati by Steve Jackson Games. After several years, the company ran out of money and laid off most of its employees; Bram Cohen went on to create BitTorrent and Zooko Wilcox-O'Hearn created Mnet out of MojoNation's source code and contributed later to the Tahoe-LAFS. Mojonation ceased operation as a commercial enterprise in February 2002, when it was replaced by the noncommercial Mnet project. MojoNation At the time it was first publicly released, MojoNation included several notable features: Evil Geniuses Transport Protocol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
9 (number)
9 (nine) is the natural number following and preceding . Evolution of the Arabic digit In the beginning, various Indians wrote a digit 9 similar in shape to the modern closing question mark without the bottom dot. The Kshatrapa, Andhra and Gupta started curving the bottom vertical line coming up with a -look-alike. The Nagari continued the bottom stroke to make a circle and enclose the 3-look-alike, in much the same way that the sign @ encircles a lowercase ''a''. As time went on, the enclosing circle became bigger and its line continued beyond the circle downwards, as the 3-look-alike became smaller. Soon, all that was left of the 3-look-alike was a squiggle. The Arabs simply connected that squiggle to the downward stroke at the middle and subsequent European change was purely cosmetic. While the shape of the glyph for the digit 9 has an ascender in most modern typefaces, in typefaces with text figures the character usually has a descender, as, for example, in . The mod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zooko Wilcox-O'Hearn
Zooko Wilcox-O'Hearn (born Bryce Wilcox; 13 May 1974 in Phoenix, Arizona), is an American Colorado-based computer security specialist, self-proclaimed cypherpunk, and CEO of the Electric Coin Company (ECC), a for-profit company leading the development of Zcash. Biography He is known for the Tahoe Least-Authority File Store (or Tahoe-LAFS), a secure, decentralized, fault-tolerant filesystem released under GPL and the TGPPL licenses. He is the creator of the Transitive Grace Period Public Licence (TGPPL). Wilcox-O'Hearn is the designer of multiple network protocols that incorporate concepts such as self-contained economies and secure reputation systems. He is a member of the development team of ZRTP and the BLAKE2 cryptographic hash function. Zooko's triangle is named after Wilcox-O'Hearn, who described the schema that relates three desirable properties of identifiers in 2001. Wilcox-O'Hearn was founder and CEO of Least Authority Enterprises in Boulder, Colorado where he is no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
26 (number)
26 (twenty-six) is the natural number following 25 and preceding 27. In mathematics *26 is the only integer that is one greater than a square (5 + 1) and one less than a cube (3 − 1). *26 is a telephone number, specifically, the number of ways of connecting 5 points with pairwise connections. *There are 26 sporadic groups. *The 26-dimensional Lorentzian unimodular lattice II25,1 plays a significant role in sphere packing problems and the classification of finite simple groups. In particular, the Leech lattice is obtained in a simple way as a subquotient. *26 is the smallest number that is both a nontotient and a noncototient number. *There are 26 faces of a rhombicuboctahedron. *When a 3 × 3 × 3 cube is made of 27 unit cubes, 26 of them are viewable as the exterior layer. Also a 26 sided polygon is called an icosihexagon. *φ(26) = φ(σ(26)). Properties of its positional representation in certain radixes Twenty-six is a repdigit in base three (2223) and in base 12 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
8 (number)
8 (eight) is the natural number following 7 and preceding 9. In mathematics 8 is: * a composite number, its proper divisors being , , and . It is twice 4 or four times 2. * a power of two, being 2 (two cubed), and is the first number of the form , being an integer greater than 1. * the first number which is neither prime nor semiprime. * the base of the octal number system, which is mostly used with computers. In octal, one digit represents three bits. In modern computers, a byte is a grouping of eight bits, also called an wikt:octet, octet. * a Fibonacci number, being plus . The next Fibonacci number is . 8 is the only positive Fibonacci number, aside from 1, that is a perfect cube. * the only nonzero perfect power that is one less than another perfect power, by Catalan conjecture, Mihăilescu's Theorem. * the order of the smallest non-abelian group all of whose subgroups are normal. * the dimension of the octonions and is the highest possible dimension of a normed divisio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
