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Energy-Efficient Ethernet
In computer networking, Energy-Efficient Ethernet (EEE) is a set of enhancements to twisted-pair, twinaxial, backplane, and optical fiber Ethernet physical-layer variants that reduce power consumption during periods of low data activity. The intention is to reduce power consumption by 50% or more, while retaining full compatibility with existing equipment. The Institute of Electrical and Electronics Engineers (IEEE), through the IEEE 802.3az task force, developed the standard. The first study group had its call for interest in November 2006, and the official standards task force was authorized in May 2007. The IEEE ratified the final standard in September 2010. Some companies introduced technology to reduce the power required for Ethernet before the standard was ratified, using the name Green Ethernet. Some energy-efficient switch integrated circuits were developed before the IEEE 802.3az Energy-Efficient Ethernet standard was finalized. Potential savings In 2005, all th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Energy Efficient Ethernet
In computer networking, Energy-Efficient Ethernet (EEE) is a set of enhancements to twisted-pair, twinaxial, backplane, and optical fiber Ethernet physical-layer variants that reduce power consumption during periods of low data activity. The intention is to reduce power consumption by 50% or more, while retaining full compatibility with existing equipment. The Institute of Electrical and Electronics Engineers (IEEE), through the IEEE 802.3az task force, developed the standard. The first study group had its call for interest in November 2006, and the official standards task force was authorized in May 2007. The IEEE ratified the final standard in September 2010. Some companies introduced technology to reduce the power required for Ethernet before the standard was ratified, using the name Green Ethernet. Some energy-efficient switch integrated circuits were developed before the IEEE 802.3az Energy-Efficient Ethernet standard was finalized. Potential savings In 2005, all th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fast Ethernet
In computer networking, Fast Ethernet physical layers carry traffic at the nominal rate of 100 Mbit/s. The prior Ethernet speed was 10 Mbit/s. Of the Fast Ethernet physical layers, 100BASE-TX is by far the most common. Fast Ethernet was introduced in 1995 as the IEEE 802.3u standard and remained the fastest version of Ethernet for three years before the introduction of Gigabit Ethernet. The acronym ''GE/FE'' is sometimes used for devices supporting both standards. Nomenclature The "100" in the media type designation refers to the transmission speed of 100 Mbit/s, while the "BASE" refers to baseband signaling. The letter following the dash ("T" or "F") refers to the physical medium that carries the signal (twisted pair or fiber, respectively), while the last character ("X", "4", etc.) refers to the line code method used. Fast Ethernet is sometimes referred to as 100BASE-X, where "X" is a placeholder for the FX and TX variants. General design Fast Ethernet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethernet
Ethernet () is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 1983 as IEEE 802.3. Ethernet has since been refined to support higher bit rates, a greater number of nodes, and longer link distances, but retains much backward compatibility. Over time, Ethernet has largely replaced competing wired LAN technologies such as Token Ring, FDDI and ARCNET. The original 10BASE5 Ethernet uses coaxial cable as a shared medium, while the newer Ethernet variants use twisted pair and fiber optic links in conjunction with switches. Over the course of its history, Ethernet data transfer rates have been increased from the original to the latest , with rates up to under development. The Ethernet standards include several wiring and signaling variants of the OSI physical layer. Systems communicating over Ethernet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEEE 802
IEEE 802 is a family of Institute of Electrical and Electronics Engineers (IEEE) standards for local area networks (LAN), personal area network (PAN), and metropolitan area networks (MAN). The IEEE 802 LAN/MAN Standards Committee (LMSC) maintains these standards. The IEEE 802 family of standards has had twenty-four members, numbered 802.1 through 802.24, with a working group of the LMSC devoted to each. However, not all of these working groups are currently active. The IEEE 802 standards are restricted to computer networks carrying variable-size packets, unlike cell relay networks, for example, in which data is transmitted in short, uniformly sized units called cells. Isochronous signal networks, in which data is transmitted as a steady stream of octets, or groups of octets, at regular time intervals, are also outside the scope of the IEEE 802 standards. The number 802 has no significance: it was simply the next number in the sequence that the IEEE used for standards projects. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autonomous Peripheral Operation
In computing, autonomous peripheral operation is a hardware feature found in some microcontroller architectures to off-load certain tasks into embedded autonomous peripherals in order to minimize latencies and improve throughput in hard real-time applications as well as to save energy in ultra-low-power designs. Overview Forms of autonomous peripherals in microcontrollers were first introduced in the 1990s. Allowing embedded peripherals to work independently of the CPU and even interact with each other in certain pre-configurable ways off-loads event-driven communication into the peripherals to help improve the real-time performance due to lower latency and allows for potentially higher data throughput due to the added parallelism. Since 2009, the scheme has been improved in newer implementations to continue functioning in sleep modes as well, thereby allowing the CPU (and other unaffected peripheral blocks) to remain dormant for longer periods of time in order to save energy. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Power Over Ethernet
Power over Ethernet, or PoE, describes any of several standards or ad hoc systems that pass electric power along with data on twisted-pair Ethernet cabling. This allows a single cable to provide both data connection and electrical power to devices such as wireless access points (WAPs), Internet Protocol (IP) cameras, and voice over Internet Protocol (VoIP) phones. There are several common techniques for transmitting power over Ethernet cabling. Three of them have been standardized by Institute of Electrical and Electronics Engineers (IEEE) standard IEEE 802.3 since 2003. These standards are known as ''alternative A'', ''alternative B'', and ''4PPoE''. For 10BASE-T and 100BASE-TX, only two of the four signal pairs in typical Cat 5 cable are used. Alternative B separates the data and the power conductors, making troubleshooting easier. It also makes full use of all four twisted pairs in a typical Cat 5 cable. The positive voltage is applied to pins 4 and 5, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
One Watt Initiative
The One Watt Initiative is an energy-saving initiative by the International Energy Agency (IEA) to reduce standby power-use by any appliance to no more than one watt in 2010, and 0.5 watts in 2013, which has given rise to regulations in many countries and regions. Standby power Standby power, informally called ''vampire'' or ''phantom power,'' refers to the electricity consumed by many appliances when they are switched off or in standby mode. The typical standby power per appliance is low (typically from less than 1 to 25 W), but, when multiplied by the billions of appliances in houses and in commercial buildings, standby losses represent a significant fraction of total world electricity use. According to Alan Meier, a staff scientist at the Lawrence Berkeley National Laboratory, standby power before the One Watt Initiative proposals were implemented as regulations accounted for as much as 10% of household power consumption. A study in France found that standby power accounted f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Computing
Green computing, green IT, or ICT sustainability, is the study and practice of environmentally sustainable computing or IT. The goals of green computing are similar to green chemistry: reduce the use of hazardous materials, maximize energy efficiency during the product's lifetime, the recyclability or biodegradability of defunct products and factory waste. Green computing is important for all classes of systems, ranging from handheld systems to large-scale data centers. Many corporate IT departments have green computing initiatives to reduce the environmental effect of their IT operations. Yet it is also clear that the environmental footprint of the sector is significant, estimated at 5-9% of the world's total electricity use and more than 2% of all emissions. Data centres and telecommunications will need to become more energy efficient, reuse waste energy, and use more renewable energy sources. They can and should become climate neutral by 2030. Origins In 1992, the U.S. Enviro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wi-Fi
Wi-Fi () is a family of wireless network protocols, based on the IEEE 802.11 family of standards, which are commonly used for local area networking of devices and Internet access, allowing nearby digital devices to exchange data by radio waves. These are the most widely used computer networks in the world, used globally in home and small office networks to link desktop and laptop computers, tablet computers, smartphones, smart TVs, printers, and smart speakers together and to a wireless router to connect them to the Internet, and in wireless access points in public places like coffee shops, hotels, libraries and airports to provide visitors with Internet access for their mobile devices. ''Wi-Fi'' is a trademark of the non-profit Wi-Fi Alliance, which restricts the use of the term ''Wi-Fi Certified'' to products that successfully complete interoperability certification testing. the Wi-Fi Alliance consisted of more than 800 companies from around the world. over 3.05 billion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TCP Offload Engine
TCP offload engine (TOE) is a technology used in some network interface cards (NIC) to offload processing of the entire TCP/IP stack to the network controller. It is primarily used with high-speed network interfaces, such as gigabit Ethernet and 10 Gigabit Ethernet, where processing overhead of the network stack becomes significant. TOEs are often used as a way to reduce the overhead associated with Internet Protocol (IP) storage protocols such as iSCSI and Network File System (NFS). Purpose Originally Transmission Control Protocol, TCP was designed for unreliable low speed networks (such as early dial-up modems) but with the growth of the Internet in terms of Internet backbone, backbone transmission speeds (using Optical Carrier, Gigabit Ethernet and 10 Gigabit Ethernet links) and faster and more reliable access mechanisms (such as digital subscriber line, DSL and cable modems) it is frequently used in data centers and desktop personal computer, PC environments at speeds of over 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Layer
In the seven-layer OSI model of computer networking, the physical layer or layer 1 is the first and lowest layer; The layer most closely associated with the physical connection between devices. This layer may be implemented by a PHY chip. The physical layer provides an electrical, mechanical, and procedural interface to the transmission medium. The shapes and properties of the electrical connectors, the frequencies to broadcast on, the line code to use and similar low-level parameters, are specified by the physical layer. Role The physical layer defines the means of transmitting a stream of raw bits over a physical data link connecting network nodes. The bitstream may be grouped into code words or symbols and converted to a physical signal that is transmitted over a transmission medium. The physical layer consists of the electronic circuit transmission technologies of a network. It is a fundamental layer underlying the higher level functions in a network, and can be imple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Dollar
The United States dollar ( symbol: $; code: USD; also abbreviated US$ or U.S. Dollar, to distinguish it from other dollar-denominated currencies; referred to as the dollar, U.S. dollar, American dollar, or colloquially buck) is the official currency of the United States and several other countries. The Coinage Act of 1792 introduced the U.S. dollar at par with the Spanish silver dollar, divided it into 100 cents, and authorized the minting of coins denominated in dollars and cents. U.S. banknotes are issued in the form of Federal Reserve Notes, popularly called greenbacks due to their predominantly green color. The monetary policy of the United States is conducted by the Federal Reserve System, which acts as the nation's central bank. The U.S. dollar was originally defined under a bimetallic standard of (0.7735 troy ounces) fine silver or, from 1837, fine gold, or $20.67 per troy ounce. The Gold Standard Act of 1900 linked the dollar solely to gold. From 1934, it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
