| L1 Cache |
Level 1 (L1) cache, also known as primary cache, is a memory cache built into the CPU.L1 cache is used by the central processing unit of a computer to reduce the average time to access memory. The cache is a smaller, faster memory which stores copies of the data from the most frequently used main memory locations. As long as most memory accesses are to cached memory locations, the average latency of memory accesses will be closer to the cache latency than to the latency of main memory.
|
| L2 Cache |
Level 2 (L2) cache, also known as secondary cache or RAM cache, is the cache memory external to the CPU. L2 cache memory resides on a separate chip from the microprocessor chip. L2 cache contains a subset of the contents of main memory. The design of the memory and L2 cache is a significant way designers differentiate their systems.
|
| L3 Cache |
Level 3 cache is the third-fastest cache memory available to a CPU. It usually consists of SRAM chips located on the motherboard. The "L3" indicates that the CPU attempts to access this cache after accessing the L1 and L2 cache. Level 3 cache is now the name for the extra cache built into motherboards between the microprocessor and the main memory.
|
| LADDR: Layered Device Driver |
Layered Device Driver (LADDR) is s SCSI device driver architecture used in early versions of OS/2.
|
| Lambda |
Lambda is the 11th letter of the Greek alphabet. In physics, Lambda is often used as the symbol for wavelength in electromagnetic wave systems.
|
| LAN Free Backup |
LAN free backup refers to backing up data without transferring it across the LAN or WAN. Instead, LAN free backup architecture uses a server or a NAS storage device with backup storage (tapes, MO, CD, etc.) directly attached. A common approach is to use a SAN that connects the disks and backup storage via a Fibre Channel switch. A variation of LAN free backup is "server free backup." Server free backup uses a SAN, but instead of having a backup server manage the backup operation, it uses a simpler device called a "data mover." The data mover can be embedded into the backup storage device itself or be a separate unit that also handles conversion from Fibre Channel to SCSI.
|
| LAN Switch |
LAN Switch is specially designed and optimized for local area network switching that forwards packets between data-link segments. Most LAN switches forward traffic based on MAC addresses. LAN switches are often categorized according to the method they use to forward traffic: cut-through packet switching or store-and-forward packet switching. Multilayer switches are an intelligent subset of LAN switches. LAN switches are available for Ethernet, Fast Ethernet, Token Ring and FDDI.
|
| Laptop Computer |
A laptop computer, also known as notebook computer, is a small mobile personal computer. Laptops usually run on batteries, but also from adapters which also charge the battery using mains electricity. Laptops are capable of many of the same tasks that desktop computers perform, although they are typically less powerful for the same price. Laptops contain components that are similar to those in their desktop counterparts and perform the same functions but are miniaturized and optimized for mobile use and efficient power consumption.
|
| Laser |
Laser is the light amplification by simulated emission of radiation. Analog transmission device in which a suitable active material is excited by an external stimulus to produce a narrow beam of coherent light that can be modulated into pulses to carry data. Networks based on laser technology are sometimes run over SONET.
|
| Laser Printer |
Laser printer, the best resolution printers so far, utilizes a laser beam to produce an image on a drum. The light of the laser alters the electrical charge on the drum wherever it hits. The drum is then rolled through a reservoir of toner, which is picked up by the charged portions of the drum. Finally, the toner is transferred to the paper through a combination of heat and pressure. A printer that uses a laser beam to produce high quality text and graphic images.
|
| Layer 2 Switch |
Layer 2 switch is a local area network switch that forwards traffic based on MAC layer (Ethernet or Token Ring) addresses.
|
| Layer 3 Switch |
Layer 3 switch is a network device that forwards traffic based on layer 3 information at very high speeds. Layer 3 switch uses the same routing algorithms as traditional routers do. However, Layer 3 switch performs its operations using application specific integrated circuit (ASIC) hardware, while a router does it using software in a microprocessor. A Layer 3 switch goes beyond the Layer 2 MAC addressing and routing. The Layer 3 switch looks at the incoming packet’s networking protocol. Layer 3 switching is more effectively used to segment a LAN than to provide a WAN connection. Traditionally, routers, which inspect layer 3, were considerably slower than layer 2 switches.
|
| Layer 4 Switch |
Layer 4 switch, based on the OSI "transport" layer, allows for policy-based switching such as limiting different types of traffic on specific end-user switch ports, or for prioritizing certain packet types, such as database or application server traffic. Layer 4 switches also offer a powerful combination of Network Address Translation (NAT) with higher-layer address screening. Actually, layer 4 switch may make forwarding decisions based upon information at any OSI layer from 4 through 7, depending upon the particular product. In fact, some of the so-called "Layer 4 Switches" even monitor the state of individual sessions from beginning to end, just as firewalls do, in which case they're referred to as "session switches." Therefore, it is called Layer 4 - 7 switch.
|
| Layer 7 Switch |
A Layer 7 Switch performs wire-speed processing of packet header content, not only at Layer 2 or Layer 3, but also at the transport layer (Layer 4) up through the application layer (OSI’s Layer 7). Layer 7 switch integrates routing and switching by forwarding traffic at layer 2 speed using layer 7 information. For example, an XML switch can analyze the XML tags at the application level and make forwarding decisions.
|
| LBR: Logical Blocking Addressing |
Logical Block Addressing (LBA) is a method of accessing hard disk drives. It allows IDE disks larger than 504 megabytes (1024 cylinders) in size to be fully partitioned using the MS-DOS fdisk command. Prior to this technology, ROM BIOS limitations prevented the fdisk command from using an entire hard disk that was larger than 504 megabytes (MB) in size, except by using other controller ROM routines that effectively translate the hard disk's native geometry.
|
| LCC: Leadless Chip Carrier |
Leadless Chip Carrier (LCC) is a type of packaging for integrated circuits which has no "leads", but instead rounded pins through the edges of the ceramic package.
|
| LCD Monitor |
Liguid Crystal Display (LCD) monitor uses LCD technologies for desktop monitors, notebook computers and other portable devices. The main advantage of LCD displays is that they take up less desk space and are lighter. A liquid crystal display (LCD) is a thin, flat display device made up of any number of color or monochrome pixels arrayed in front of a light source or reflector.
|
| LCD Printer |
Liguid Crystal Display (LCD) printer is an electrophotographic printer that uses a single light source directed by liquid crystal shutters. LCD printer shines a light through a liquid crystal panel. Individual pixels in the panel either let the light pass or block the light, thereby creating an image composed of dots on the drum.
|
| LCD: Liquid Crystal Display |
Liquid Crystal Display (LCD), used in digital watches and many portable computers, utilizes two sheets of polarizing material with a liquid crystal solution between them. An electric current passed through the liquid causes the crystals to align so that light cannot pass through them. Each crystal, therefore, is like a shutter, either allowing light to pass through or blocking the light.
|
| LCS: Liquid Cooling System |
Liquid Cooling System (LCS) is a type of cooling system in a computer, which consists of one or more “water blocks”, a pump, a radiator, one or more fans, tubing, cooling liquid, and may also include a reservoir and fittings. A liquid cooling system (LCS) circulates liquid through small pipes in a heat sink attached to the processor in your system. As the liquid passes through the heat sink, heat from the hot processor is transferred to the cooler liquid. The warmed liquid is then cycled to a radiator on the side or rear of the casing where it is released into the ambient air outside of the unit. The cooled liquid then travels back through the system to the CPU to continue the process.
|
| LED: Light-Emitting Diode |
A light-emitting diode (LED) is a semiconductor device that emits incoherent narrow-spectrum light when electrically biased in the forward direction. This effect is a form of electroluminescence. The color of the emitted light depends on the chemical composition of the semiconducting material used, and can be near-ultraviolet, visible or infrared. LEDs are good for displaying images because they can be relatively small, and they do not burn out. However, they require more power than LCDs.
|
| LGA 775: Land Grid Aray 775 |
LGA 775 (Land Grid Aray), also known as socket T,means that the pins are on the Motherboard, not the Processor. The Prescott is using the LGA 775 socket. Intel changed from Socket 478 to LGA 775 because Intel plans to offer a Front side bus of 1066 MHZs. The 'T' in Socket T is derived from the Tejas core which was going to replace the Prescott. Tejas is no longer a replacement.
|
| Light pen |
Light pen is an input device that utilizes a light-sensitive detector to select objects on a display screen. A light pen allows user to move the pointer and select objects on the display screen by directly pointing to the objects with the pen.
|
| Line Card |
Line Card refers to any I/O card of a network device that can be inserted in a modular chassis.
|
| Line Printer |
The Line printer is a form of high speed impact printer in which a line of type is printed at a time. Printed type is set at fixed positions and a line could consist of any number of character positions but 80 column, 128 column and 160 column variants were common. In a typical design, a fixed font character set is engraved onto the periphery of a number of print wheels, the number matching the number of columns. The wheels spin at high speed and paper and an inked ribbon are stepped past the print position. As the desired character for each column passes the print position a hammer strikes the paper and ribbon causing the desired character to be recorded on the continuous paper.
|
