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Petaoctet
The octet is a unit of digital information in computing and telecommunications that consists of eight bits. The term is often used when the term byte might be ambiguous, as the byte has historically been used for storage units of a variety of sizes. The term ''octad(e)'' for eight bits is no longer common. Definition The international standard IEC 60027-2, chapter 3.8.2, states that a byte is an octet of bits. However, the unit byte has historically been platform-dependent and has represented various storage sizes in the history of computing. Due to the influence of several major computer architectures and product lines, the byte became overwhelmingly associated with eight bits. This meaning of ''byte'' is codified in such standards as ISO/IEC 80000-13. While ''byte'' and ''octet'' are often used synonymously, those working with certain legacy systems are careful to avoid ambiguity. Octets can be represented using number systems of varying bases such as the hexadeci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Units Of Information
In computing and telecommunications, a unit of information is the capacity of some standard data storage system or communication channel, used to measure the capacities of other systems and channels. In information theory, units of information are also used to measure information contained in messages and the entropy of random variables. The most commonly used units of data storage capacity are the bit, the capacity of a system that has only two states, and the byte (or octet), which is equivalent to eight bits. Multiples of these units can be formed from these with the SI prefixes (power-of-ten prefixes) or the newer IEC binary prefixes (power-of-two prefixes). Primary units In 1928, Ralph Hartley observed a fundamental storage principle, which was further formalized by Claude Shannon in 1945: the information that can be stored in a system is proportional to the logarithm of ''N'' possible states of that system, denoted . Changing the base of the logarithm from ''b'' to a diff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Romania
Romania ( ; ro, România ) is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern, and Southeast Europe, Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, Serbia to the southwest, Moldova to the east, and the Black Sea to the southeast. It has a predominantly Temperate climate, temperate-continental climate, and an area of , with a population of around 19 million. Romania is the List of European countries by area, twelfth-largest country in Europe and the List of European Union member states by population, sixth-most populous member state of the European Union. Its capital and largest city is Bucharest, followed by Iași, Cluj-Napoca, Timișoara, Constanța, Craiova, Brașov, and Galați. The Danube, Europe's second-longest river, rises in Germany's Black Forest and flows in a southeasterly direction for , before emptying into Romania's Danube Delta. The Carpathian Mountains, which cross Roma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEC 80000-13
ISO 80000 or IEC 80000 is an international standard introducing the International System of Quantities (ISQ). It was developed and promulgated jointly by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). It serves as a style guide for the use of physical quantities and units of measurement, formulas involving them, and their corresponding units, in scientific and educational documents for worldwide use. The ISO/IEC 80000 family of standards was completed with the publication of Part 1 in November 2009. Overview , ISO/IEC 80000 comprises 13 parts, two of which (parts 6 and 13) were developed by IEC and the remaining 11 were developed by ISO, with a further three parts (15, 16 and 17) under development. Part 14 was withdrawn. Subject areas The 80000 standard currently has 13 parts. Part 1: General ISO 80000-1:2009 replaces ISO 31-0:1992 and ISO 1000:1992. It gives general information and definitions con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variable-width Encoding
A variable-width encoding is a type of character encoding scheme in which codes of differing lengths are used to encode a character set (a repertoire of symbols) for representation, usually in a computer. Most common variable-width encodings are multibyte encodings, which use varying numbers of bytes ( octets) to encode different characters. (Some authors, notably in Microsoft documentation, use the term ''multibyte character set,'' which is a misnomer, because representation size is an attribute of the encoding, not of the character set.) Early variable width encodings using less than a byte per character were sometimes used to pack English text into fewer bytes in adventure games for early microcomputers. However disks (which unlike tapes allowed random access allowing text to be loaded on demand), increases in computer memory and general purpose compression algorithms have rendered such tricks largely obsolete. Multibyte encodings are usually the result of a need to increase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hextet
In computing, a hextet, or a ''chomp'', is a sixteen-bit aggregation, or four nibbles. As a nibble typically is notated in hexadecimal format, a hextet consists of 4 hexadecimal digits. A hextet is the unofficial name for each of the 8 blocks in an IPv6 address. History Bob Bemer suggested the use of hextet for 16-bit groups in 2000. In 2011 an Internet Draft explored various alternatives for hextet such as ''quibble'', short for "quad nibble". In response to this draft, author Trefor Davies suggested the use of the word ''chomp'' because it is in line with the current denominations ''bit'', ''nibble'', ''byte''. ''Hextet'' would more properly describe a 6-bit aggregation, whereas the exact term for 16 bits should be ''hexadectet'', directly related to the term octet (for 8 bits). However, because it is harder to pronounce, the short form ''hextet'' is used—in analogy to how ''hex'' is commonly used as an abbreviation for ''hexadecimal'' in computing. This usage of ''hex'' to me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexit
Lindane, also known as ''gamma''-hexachlorocyclohexane (γ-HCH), gammaxene, Gammallin and benzene hexachloride (BHC), is an organochlorine chemical and an isomer of hexachlorocyclohexane that has been used both as an agricultural insecticide and as a pharmaceutical treatment for lice and scabies. Lindane is a neurotoxin that interferes with GABA neurotransmitter function by interacting with the GABAA receptor-chloride channel complex at the picrotoxin binding site. In humans, lindane affects the nervous system, liver, and kidneys, and may well be a carcinogen.Agency for Toxic Substances and Disease Registry, U.S. Department of Health and Human Services. Toxicologic profile for alpha-, beta, gamma- and delta-hexachlorocyclohenxane. August 2005. http://www.atsdr.cdc.gov/toxprofiles/tp43.pdf The World Health Organization classifies lindane as "moderately hazardous", and its international trade is restricted and regulated under the Rotterdam Convention on Prior Informed Consent.Wor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IPv6 Address
An Internet Protocol Version 6 address (IPv6 address) is a numeric label that is used to identify and locate a network interface of a computer or a network node participating in a computer network using IPv6. IP addresses are included in the packet header to indicate the source and the destination of each packet. The IP address of the destination is used to make decisions about routing IP packets to other networks. IPv6 is the successor to the first addressing infrastructure of the Internet, Internet Protocol version 4 (IPv4). In contrast to IPv4, which defined an IP address as a 32-bit value, IPv6 addresses have a size of 128 bits. Therefore, in comparison, IPv6 has a vastly enlarged address space. Addressing methods IPv6 addresses are classified by the primary addressing and routing methodologies common in networking: unicast addressing, anycast addressing, and multicast addressing. A unicast address identifies a single network interface. The Internet Protocol delivers packe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IPv4
Internet Protocol version 4 (IPv4) is the fourth version of the Internet Protocol (IP). It is one of the core protocols of standards-based internetworking methods in the Internet and other packet-switched networks. IPv4 was the first version deployed for production on SATNET in 1982 and on the ARPANET in January 1983. It is still used to route most Internet traffic today, even with the ongoing deployment of Internet Protocol version 6 (IPv6), its successor. IPv4 uses a 32-bit address space which provides 4,294,967,296 (232) unique addresses, but large blocks are reserved for special networking purposes. History Internet Protocol version 4 is described in IETF publication RFC 791 (September 1981), replacing an earlier definition of January 1980 (RFC 760). In March 1982, the US Department of Defense decided on the Internet Protocol Suite (TCP/IP) as the standard for all military computer networking. Purpose The Internet Protocol is the protocol that defines and enables internet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Network
A computer network is a set of computers sharing resources located on or provided by network nodes. The computers use common communication protocols over digital interconnections to communicate with each other. These interconnections are made up of telecommunication network technologies, based on physically wired, optical, and wireless radio-frequency methods that may be arranged in a variety of network topologies. The nodes of a computer network can include personal computers, servers, networking hardware, or other specialised or general-purpose hosts. They are identified by network addresses, and may have hostnames. Hostnames serve as memorable labels for the nodes, rarely changed after initial assignment. Network addresses serve for locating and identifying the nodes by communication protocols such as the Internet Protocol. Computer networks may be classified by many criteria, including the transmission medium used to carry signals, bandwidth, communications pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Protocol
The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet. IP has the task of delivering packets from the source host to the destination host solely based on the IP addresses in the packet headers. For this purpose, IP defines packet structures that encapsulate the data to be delivered. It also defines addressing methods that are used to label the datagram with source and destination information. IP was the connectionless datagram service in the original Transmission Control Program introduced by Vint Cerf and Bob Kahn in 1974, which was complemented by a connection-oriented service that became the basis for the Transmission Control Protocol (TCP). The Internet protocol suite is therefore often referred to as ''TCP/IP''. The first major version of IP, Internet Protocol Version 4 (IPv4), is the do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Electrotechnical Commission
The International Electrotechnical Commission (IEC; in French: ''Commission électrotechnique internationale'') is an international standards organization that prepares and publishes international standards for all electrical, electronic and related technologies – collectively known as "electrotechnology". IEC standards cover a vast range of technologies from power generation, transmission and distribution to home appliances and office equipment, semiconductors, fibre optics, batteries, solar energy, nanotechnology and marine energy as well as many others. The IEC also manages four global conformity assessment systems that certify whether equipment, system or components conform to its international standards. All electrotechnologies are covered by IEC Standards, including energy production and distribution, electronics, magnetics and electromagnetics, electroacoustics, multimedia, telecommunication and medical technology, as well as associated general disciplines such as t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary Prefix
A binary prefix is a unit prefix for multiples of units. It is most often used in data processing, data transmission, and digital information, principally in association with the bit and the byte, to indicate multiplication by a power of 2. As shown in the table to the right there are two sets of symbols for binary prefixes, one set established by International Electrotechnical Commission (IEC) and several other standards and trade organizations using two-letter symbols, e.g. ''Mi'' indicating with a second set established by semiconductor industry convention using one-letter symbols, e.g., ''M'' also indicating . In most contexts, industry uses the multipliers ''kilo'' (''k''), ''mega'' (''M''), ''giga'' (''G''), etc., in a manner consistent with their meaning in the International System of Units (SI), namely as powers of 1000. For example, a 500-gigabyte hard disk holds bytes, and a 1 Gbit/s (gigabit per second) Ethernet connection transfers data at nominal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
