No footnotes date June 2009 Circuitswitching is a telecommunication s technology by which two network ... circuitcircuit connecting them for the duration of the communication session before the nodes may communicate. The circuit functions as if the nodes were physically connected with an electrical circuit. The bit delay is constant during a connection, as opposed to packet switching, where packet queues may cause varying packet transfer delay . Each circuit cannot be used by other callers until the circuit is released and a new connection is set up. Even if no actual communication is taking place in a dedicated circuit that channel remains unavailable to other users. Channels that are available for new calls to be set up are said to be idle. Virtual circuitswitching is a packet switching technology that may emulate circuitswitching, in the sense that the connection is established ... that circuitswitching is used only for connecting voice circuits analog or digital . The concept ... TDM to transport the actual circuit data. Early telephone exchanges are a suitable example of circuitswitching. The subscriber would ask the operator to connect to another subscriber, whether .... With circuitswitching, and virtual circuitswitching, a route is reserved from source to destination .... Circuitswitching can be relatively inefficient because capacity is wasted on connections which ... is immediately available and capacity is guaranteed until the call is disconnected. Circuitswitching contrasts with packet switching , which splits traffic data for instance, digital representation ... and Scandinavian DATEX circuit switched data network DisplayPort See also Packet switching Message switching ... circuitos fa fr Commutation de circuits ko id Circuitswitching it Multiplazione Multiplazione ... packet switching Since the first days of the electrical telegraph telegraph it has been possible to Multiplexing ... switching is the process of segmenting a message data to be transmitted into several smaller packets ... more details
Wiktionary For electrical switching in general, see switch For telephone switching, see telephone exchange For switching of digital networks, see Packet switching For Local Area Network switching, see LAN switching For railroad turnouts, see railroad switch For the process of switching rail cars, see shunt rail disambig ja pl Komutacja ru ... more details
Circuit may mean In science and technology Circuit theory , the theory of accomplishing work by routing electrons, gas, fluids, or other matter through a loop Pneumatic circuit Hydraulic circuitCircuit complexity , study of Boolean circuit in computational complexity, a special case of circuit computer theory circuit s in computer theory. Integer circuit a mathematical object of computational complexity, another special case of circuit computer theory circuit s in computer theory. Monetary circuit theory , a heterodox theory of monetary economics also called circuitism . Cycle graph theory , a closed path, with no other repeated vertices than the starting and ending vertices. Electrical network , also called an electrical circuit Digital circuit Electronic circuit Integrated circuit Asynchronous circuit Synchronous circuit Printed circuit board PCB Series and parallel circuits Telecommunication circuitCircuit diagram Balanced circuit LC circuit Biological neural network neuronal circuit Matroid circuit, a mathematical object In government and law Circuit administrative division , an administrative country subdivision in East Asia Circuit court , the name of court systems in several common law jurisdictions In transportation and racing Circuit airfield , also called the pattern, a standard path followed by aircraft when taking off or landing Kart circuit Formula One circuits see List of Formula One circuits Race track Others Circuit film character , from the pappa ai series Circuit LCMS , local grouping of congregations in the Lutheran Church Missouri Synod Circuit film Circuit film , a 2001 gay themed film set in the world of gay circuit parties Circuit party , a gay dance event Methodist Circuit , a church governance in Methodism See also The Circuit disambig ar ca Circuit da Kredsl b de Schaltung es Circuito fr Circuit ko io Cirkuito it Circuito nl Circuit ja pl Obieg pt Circuito ru sk Obvod ur ... more details
The Circuit could refer to The Circuit TV series The Circuit TV series , an Australian drama television series The Circuit radio show The Circuit radio show , an internet radio show produced by Card Player magazine The Circuit hip hop group The Circuit 2008 film The Circuit 2008 film , a 2008 made for TV movie starring Bill Campbell and Michelle Trachtenberg The Circuit 2002 film The Circuit 2002 film and its sequels The Circuit 2 2002 and The Circuit 3 2006 , martial arts films directed by Jalal Merhi The Circuit Stories from the Life of a Migrant Child , a children s novel by Francisco Jim nez often called The Circuit The Circuit a 1986 Japanese racing game known globally as World Grand Prix See also Circuit disambiguation disambig ... more details
Cleanup date June 2007 Label switching is a technique of computer network network relaying to overcome the problems perceived by traditional internet protocol IP table switching also known as traditional layer 3 hop by hop routing ref http www.linktionary.com l label switching.html Label Switching Linktionary term Bot generated title ref . Here, the switching of network packet information technology packets occurs at a lower OSI protocols level , namely the data link layer rather than the traditional network layer . Each packet is assigned a label number and the switching takes place after examination of the label assigned to each packet. The switching is much faster than IP routing . New technologies such as Multiprotocol Label Switching MPLS use label switching. The established Asynchronous Transfer Mode ATM protocol also uses label switching at its core. According to RFC 2475 An Architecture for Differentiated Services, December 1998 Examples of the label switching or virtual circuit model include Frame Relay, ATM, and MPLS. In this model path forwarding state and traffic management or Quality of Service QoS state is established for traffic streams on each hop along a network path. Traffic aggregates of varying granularity are associated with a label switched path at an ingress node, and packets cells within each label switched path are marked with a forwarding label that is used to look up the next hop node, the per hop forwarding behavior, and the replacement label at each hop. This model permits finer granularity resource allocation to traffic streams, since label values ... Virtual circuit Category Computer networking compu network stub de Label Switching ... switching semantics govern the next hop selection, allowing a traffic stream to follow a specially engineered path through the network. br br A related topic is Multilayer Switching, which discusses ... l label switching.html linktionary.com http www.linktionary.com l label switching.html , Label Switching ... more details
See also Short message service SMS circuitswitching Message Oriented Middleware message oriented middleware ...In telecommunications , message switching was the precursor of packet switching , where messages were routed in their entirety, one hop at a time. It was first introduced by Leonard Kleinrock in 1961. Message switching systems are nowadays mostly implemented over packet switched or circuit switched data ... application for Message Switching. A delay in delivering email is allowed unlike real time ... of message switching systems. E mail is another example of a message switching system. When this form of switching is used, no physical path is established in advance in between sender and receiver. Instead, when the sender has a block of data to be sent, it is stored in the first switching ..., since conversions are done by the message switching networks. A message switch is transactional ... form or an entirely different form at the receive end. Message switching multiplexes data from different sources onto a common facility. A message switch is a one of the switching technology. In message switching, when a message consists of a block of data to be sent, it is stored in the first switching office i.e. router and then forwarded later, one hop at a time. Each block is received ... and forward network. Store and forward delays Since message switching stores each message ... to any propagation delays which will be experienced along the message path. In a message switching ... in a queue with any other messages for the same route and retransmitted when the required circuit becomes free. Message switching is thus an example of a delay system or a queuing system. Message switching is still used for telegraph traffic and a modified form of it, known as packet switching, is used extensively for data communications. Advantages The advantages to Message Switching are Data ... Computer networking telecomm term stub mk Message switching pl Komutacja wiadomo ci pt Comuta o de ... more details
Gain switching is a technique in optics by which a laser can be made to produce pulses of light of extremely short duration, of the order of picoseconds 1 E 12 s 10 sup 12 sup s . ref K. Y. Lau, Gain switching of semiconductor injection lasers ,Appl. Phys. Lett.,vol. 52, iss. 4, pp. 257 259 1988 ref ref P. Vasil ev, Ultrafast Laser Diodes Fundamentals and Applications , Artech House, London, 1995 ref div style float right width 424px margin 0 0 1em 1em Image gainswitchpulse.png Pulse generated by gain switching div In a semiconductor laser , the optical pulses are generated by injecting a large number of carriers electrons into the active region of the device, bringing the carrier density within that region from below to above the lasing threshold . When the carrier density exceeds that value, the ensuing stimulated emission results in the generation of a large number of photons. However, carriers are depleted as a result of stimulated emission faster than they are injected. So the carrier density eventually falls back to below lasing threshold which results in the termination of the optical output. If carrier injection has not ceased during this period, then the carrier density in the active region can increase once more and the process will repeat itself. The figure on the right shows a typical pulse generated by gain switching with a sinusoidal injection current at 250 MHz producing a pulse of approximately 50 ps. The carrier density is depleted during the pulse ... diode circuit, a single 50 ps light pulse can be generated. For solid state and dye laser s, gain switching or synchronous pumping usually involves the laser gain medium being Laser pumping ... present in the laser for a short time, which results in a pulsed output. Q switching is more commonly ... can be achieved. The term gain switching derives from the fact that the optical gain is negative when ... also Q switching Modelocking References Reflist DEFAULTSORT Gain Switching Category Laser science ... more details
This article addresses packet switching in computer network s. LAN switching is a form of packet switching used in local area network s. Switching technologies are crucial to network design, as they allow ... 2 switching Layer 2 switching is hardware based, which means it uses the media access control address ... frames. Switches use application specific integrated circuit s ASICs to build and maintain filter ... bridge bridge . Layer 2 switching provides the following Hardware based bridging MAC Wire speed High speed Low latency Low cost Layer 2 switching is highly efficient because there is no modification ... is passing through dissimilar media such as from Ethernet to FDDI . Layer 2 switching is used for workgroup ... network design with more network segments than traditional 10BaseT shared networks. Layer 2 switching ... replace routers in the internetwork. Layer 3 switching The only difference between a network layer ... based packet switching. However, some traditional routers can have other hardware functions as well ... they handle high performance LAN traffic and can cost effectively replace routers. Layer 3 switching ... specific integrated circuit ASICs . Layer 3 switches really are no different functionally than ... Base MIB information Provide Security The benefits of layer 3 switching include the following Hardware based packet forwarding High performance packet switching High speed scalability Low Lag latency Lower per port cost Flow accounting Security Quality of service QoS Layer 4 switching Layer 4 switching is considered a hardware based layer 3 switching technology that can also consider the application used for example, Telnet or FTP . Layer 4 switching provides additional routing above ... example is accounting information gathered by NetFlow switching in Cisco s higher end routers. The largest benefit of layer 4 switching is that the network administrator can configure a layer 4 switch ..., based on the need for video conferencing. Multi layer switching MLS main Multilayer switch Multi layer ... more details
In computational complexity theory , H stad s switching lemma is a key tool for proving lower bounds on the size of constant depth Boolean circuits . Using the switching lemma, harvtxt H stad 1987 showed that Boolean circuits of depth k in which only AND, OR, and NOT gates are allowed require size math exp left Omega left n frac 1 k 1 right right math for computing the parity function . The switching lemma says that depth 2 circuits in which some fraction of the variables have been set randomly depend with high probability only on very few variables after the restriction. The name of the switching lemma stems from the following observation Take an arbitrary formula in conjunctive normal form , which is in particular a depth 2 circuit. Now the switching lemma guarantees that after setting some variables randomly, we end up with a Boolean function that depends only on few variables, i.e., it can be computed by a decision tree of some small depth math d math . This allows us to write the restricted function as a small formula in disjunctive normal form . A formula in conjunctive normal form hit by a random restriction of the variables can therefore be switched to a small formula in disjunctive normal form. The original proof of the switching lemma harv H stad 1987 involves an argument with conditional probabilities . Arguably simpler proofs have been subsequently given by harvtxt Razborov 1993 and harvtxt Beame 1994 . For an introduction, see Chapter 14 in harvtxt Arora Barak 2009 . References refbegin Citation last1 Arora first1 Sanjeev authorlink1 Sanjeev Arora last2 Barak first2 Boaz title Computational Complexity A Modern Approach url http www.cs.princeton.edu theory complexity publisher Cambridge University Press Cambridge year 2009 isbn 978 0 521 42426 4 author Sanjeev Arora, Boaz Barak ref harv citation last Beame first Paul title A Switching Lemma Primer journal Manuscript ... complexity theory Category Circuit complexity ... more details
The term switching station may refer to a Rail yard railroad switching station . a telephone exchange telephone switching station . a Electrical substation substation , with only one voltage level, whose only function are switching actions. disambig ... more details
load in the network. Packet switching contrasts with another principal networking paradigm, circuitswitching , a method which sets up a limited number of dedicated connections of constant bit rate ... fees, for example in cellular communication, circuitswitching is characterized by a fee per time unit of connection time, even when no data is transferred, while packet switching is characterized by a fee per unit of information. Two major packet switching modes exist Connectionless communication connectionless packet switching, also known as datagram switching, and Connection oriented communication connection oriented packet switching, also known as virtual circuitswitching. In the first ... nodes can be either connectionless based on datagram messages , or virtual circuitswitching ... switching methods, it provided virtual circuit s to the user. These virtual circuits carry variable ... is a virtual circuit technology, which uses fixed length cell relay connection oriented packet switching ... Relay provide connection oriented packet switching, also known as virtual circuitswitching. A major ... as an alternative to circuit mode terminal switching, and for automated teller machine s. Frame ...Packet switching is a digital networking communications method that groups all transmitted data &ndash ... packets . Packet switching features delivery of variable bit rate data streams sequences of packets ... and connection oriented packet switching below . Packet mode communication may be utilized ... packet mode multiple access scheme. Multiplex techniques History The concept of switching small ... conducted early research in queueing theory which would be important in packet switching, and published a book in the related field of digital message switching without the packets in 1961 he also ..., the ARPANET . Baran developed the concept of message block switching during his research at the RAND ... Invents Packet Switching work Living Internet date 2000 01 07 url http www.livinginternet.com i ... more details
or washaway detector is buried in the earth embankment, and opens a circuit should a landslide occur. It is not possible to guarantee that the wet earth of the embankment will not complete the circuit which is supposed to break. If the circuit is double cut with positive and negative wires, any ... The Clapham Junction rail crash of 1988 was caused in part by the lack of double switching known ... in part by a single switched safety circuit for the baggage door mechanism. Failure of the wiring insulation in that circuit allowed the baggage door to be unlocked by a false feed, leading to a catastrophic ..., with unpredictable effects. A similar crosstalk problem occurred when using Phantom circuit ... more details
Unreferenced date October 2008 An adaptive switch is designed to operate in cut through mode cut through switching normally but if a port s error rate jumps too high, the switch automatically reconfigures the port to run in store and forward mode This optimizes the switch s performance by providing higher speed cut through switching switching if error rates are low but higher throughput Store and forward switching if error rates are high Typically done on a port by port basis See also Network switch Ethernet Store and forward Fragment free cut through switching Category Computer networking compu hardware stub cs Adaptive switching ... more details
In a packet switched computer network network , burst switching is a capability in which each network switch extracts routing instructions from an incoming Packet information technology packet header information technology header to establish and maintain the appropriate switch telecommunication connection connection for the duration of the packet, following which the connection is automatically released. In concept, burst switching is similar to connectionless mode transmission , but differs in that burst switching implies an intent to establish the switch connection in near real time so that only minimum buffering is required at the node networking node switch. A variant of burst switching used in optical networks is optical burst switching . Source from Federal Standard 1037C compu network stub Category Computer networks ... more details
In building wiring , multiway switching is interconnection of two or more light switch es to control lighting from more than one location. This allows lighting in a hallway or stairwell to be controlled from either end. Three way and four way This article follows American usage. Readers in the UK should read two way for the American three way and intermediate or crossover switch for the American four way . ref http www.ultimatehandyman.co.uk three way lighting.htm Usage on Ultimate Handyman UK website ref ref http www.diyhowto.co.uk projects two way lighting.htm DIY Howto UK website . ref Three way and four way switches make it possible to control a light from multiple locations, such as the top and bottom of a stairway, or either end of a long hallway. These switches are externally similar to single pole switches, but have extra connections which allow two circuits to be controlled. Toggling the switch disconnects one circuit and connects the other. Electrically, a three way switch is a single pole, double throw SPDT switch . By connecting two of these switches together, toggling either switch changes the state of the light from off to on, or on to off. A four way switch has two pairs of terminals which it connects either straight through, or crossed over. By connecting one or more four way switches in line with three way switches at either end, the light can be controlled from .... Two locations Switching a load on or off from two locations for instance, turning a light on or off ... and two three way switches. It allows for a hot receptacle at both ends of the circuit as well ... circuit to be controlled from either end. The alternative system is to join the three terminals of one ... 4 way switches position 7.svg File 4 way switches position 8.svg As mentioned above, the above circuit can be extended by using multiple 4 way switches between the 3 way switches to extend switching ... Electrical wiring de Wechselschaltung fr Circuit va et vient nl Wisselschakeling ... more details
Wormhole flow control , also called wormhole switching or wormhole routing is a system of simple flow control in computer networking based on known fixed links. It is a subset of flow control methods called Flit Buffer Flow Control. ref cite book author William James Dally and Brian Towles title Principles and Practices of Interconnection Networks chapter 13.2.1 publisher Morgan Kaufmann Publishers, Inc year 2004 isbn 9780122007514 ref Actually, switching is the more appropriate term than routing. ref cite book author John L. Hennessy and David A. Patterson title Computer Architecture A Quantitative Approach edition Fourth Edition chapter Appendix E.5 publisher Morgan Kaufmann Publishers, Inc year 2006 isbn 9780123704900 ref Routing defines the route or path taken to reach the destination. The wormhole technique does not dictate the route to the destination but decides when the packet moves forward from a router. cut through Cut through switching commonly called Virtual Cut through, operates in a similar manner, the major difference being that cut through flow control allocates buffers and channel bandwidth on a packet level, while wormhole flow control does this on the flit level. In most respects, wormhole is very similar to Asynchronous Transfer Mode ATM or MPLS forwarding, with the exception that the cell does not have to be queue data structure queue d. Large network packets are broken into small pieces called flits fl ow control dig its . The first flit, called the header flit holds information about this packet s route namely the destination address and sets up the routing ... up a circuit to the next router, and then bows out of the conversation. This reduces latency delay noticeably compared to store and forward store and forward switching that waits for the whole packet ..., or on a lower level, even functional units can be connected in a network on a single Integrated Circuit ... port. See also IEEE 1355 SpaceWire References reflist DEFAULTSORT Wormhole Switching Category Flow ... more details
No footnotes date August 2009 Lead too short date August 2009 Switching barriers or switching costs are terms ... s changing of suppliers. In many market s, consumer s are forced to incur cost s when switching from one Supply and demand supplier to another. These costs are called switching costs and can come in many different shapes. Definition The definition of switching costs is quite broad. Thompson and Cats Baril 2002 Citation needed date April 2009 defines switching costs as the costs associated with switching supplier , while Farrell and Klemperer 2007 write that a consumer faces a switching ... seller . As these definitions indicate, switching costs can arise for several different reasons. Examples of switching costs include the effort needed to inform friends and relatives about a new telephone ... switching to a new electricity provider. Types of switching costs include exit fees, search costs ..., the psychological, emotional, and social costs of switching are often overlooked or underestimated ... to hook into a phone line. Switching costs are a major reason for pursuing orders of magnitude ... strategy has been called Andrew Grove Andy Grove s 10x rule. Where switching costs for a buyer are prohibitively ..., a bilateral monopoly . However, Shalev and Asbjornsen found that Switching Costs is not a relevant ... be avoided in the public sector, switching costs are always incurred, and so switching costs would not be a relevant ..., 10 3 428 452. ref Competition, collective switching costs, and market performance Switching costs affect competition . When a consumer faces switching costs, the rational consumer will not switch to the Supply and demand supplier offering the lowest price if the switching costs in terms of monetary ... from switching. QWERTY example Competition is also influenced by collective switching costs, especially in markets with strong network effects . Collective switching costs are the combined switching costs of all users in a particular market. For example, the QWERTY keyboard layout illustrates ... more details
Prey switching is Frequency dependent selection frequency dependent predation, where the predator preferentially ... morphs. In comparison, prey switching has been used when describing the choice between different .... Soc. B 319, 485 503 ref Definition The term switching was first coined by the ecologist Murdoch ... type of prey. ref Murdoch,W.W. 1969 Switching in generalist predators experiments on prey specificity ... prey switching has mainly been used by ecologists, while apostatic selection has been used ... dependent selection. One of the ways prey switching has been identified and defined is when a predator ... which are rare. The definition of preference will therefore impact on understanding switching. The most .... c is the preference for prey type 1. If c increases with N1 N2 prey switching is presumed to occur. The opposite of prey switching is when a predator eats disproportionately more of the most rare prey ... prey switching, or anti apostatic selection when it refers to the choice between different morphs. Prey switching has been in the scientific literature for around 40 years, and since initial work, Hassell suggests that interest has fallen as prey switching as it is hard to demonstrate whether it has ... of frequency dependent predation Switching in the 15 spines Stickleback, Spinachia spinachia ... of switching in some general predators. Am. Nat. 110, 317 320 ref It has been argued that frequency ... 186 ref These ultimate mechanisms help to demonstrate how prey switching and apostatic selection ... of when a consumer feeds can account for switching behaviour. In experiments with Guppies the switching behaviour displayed was due to the choice of patch. ref Murdoch, W.W. et al. 1974 Switching in Predatory Fish. Ecology 56, 1094 1105 ref Likewise the switching behaviour of stoneflies was due to the time they were active. ref Elliott, J.M. 2004 Prey switching in four species of carnivorous ... switching which prey it eats. ref name hughes&1993 Real suggests that a mechanism similar to search ... more details
Phenotypic switching a.k.a. phenotypic dimorphism is switching between two cell types. An example is Candida albicans , which, when it infects host tissue, switches from the usual unicellular yeast like form of into an invasive, multicellular filamentous form. ref cite journal author Kumamoto CA, Vinces MD title Contributions of hyphae and hypha co regulated genes to Candida albicans virulence journal Cell. Microbiol. volume 7 issue 11 pages 1546 54 year 2005 pmid 16207242 doi 10.1111 j.1462 5822.2005.00616.x ref This switching between two cell types is known as dimorphism. Phenotypic switching in C. albicans include the switch from white cells to opaque cells in need for sexual mating. References Reflist External links cite journal author Neville SE, Baigent S, Lowry PJ title Are Hox genes responsible for the phenotypic switching and zonation of the adult adrenal cortex? journal Endocrine Abstracts volume 2 pages 52 date December 2001 url http www.endocrine abstracts.org ea 0002 ea0002p52.htm cite journal author D Souza CA, Heitman J title It infects me, it infects me not phenotypic switching in the fungal pathogen Cryptococcus neoformans journal J. Clin. Invest. volume 108 issue 11 pages 1577 8 year 2001 month December pmid 11733551 pmc 200997 doi 10.1172 JCI14497 url http www.jci.org cgi content full 108 11 1577 cite journal author Sonneborn A, Tebarth B, Ernst JF title Control of white opaque phenotypic switching in Candida albicans by the Efg1p morphogenetic regulator journal Infect. Immun. volume 67 issue 9 pages 4655 60 date 1 September 1999 pmid 10456912 pmc 96790 url http iai.asm.org cgi pmidlookup?view long&pmid 10456912 cite conference author Javan C, Shaunak S title Repeated phenotypic switching of HIV 1 in AIDS patients sampled regularly over 2 years. booktitle 4th Conference on Retroviruses and Opportunistic Infections date January 22 26, 1997 location Washington, DC url http www.aegis.com conferences croi 1997 450.html DEFAULTSORT Phenotypic Switching ... more details
language sociolinguistics In linguistics , code switching is the concurrent use of more than one language ... other. Thus, code switching is the use of more than one linguistic variety in a manner consistent with the syntax and phonology of each variety. Code switching is distinct from other language contact ... language. On the other hand, speakers practice code switching when they are each fluent in both languages. Code mixing is a thematically related term, but the usage of the terms code switching and code ... mixing to denote the formal linguistic properties of said language contact phenomena, and code switching ... Constraints on code switching how universal are they? editor1 last Li Wei title The Bilingualism ... publisher Routledge ref In the 1940s and the 1950s many scholars called code switching a sub standard ... switching is also used outside the field of linguistics. Some scholars of literature use the term ... Zone Code Switching Strategies by Latino a Writers journal Melus volume 32 number 1 year 2007 pages 75 96 ref In popular usage code switching is sometimes used to refer to relatively stable ... switching is sometimes used to refer to switching among dialect s, style shifting styles or Register ... Multilingual Matters pages 157 167 isbn 185359167X ref Social motivations for code switching Code mixing links here Code switching relates to, and sometimes Indexicality indexes social group membership ... code switching behaviours and Social class class , ethnicity , and other social positions. ref See ..., scholars in interactional linguistics and conversation analysis have studied code switching ... and How Questions in the Analysis of Conversational Codeswitching title Code Switching in Conversation ... Sequential Versus Identity Related Explanation in Code Switching title Code Switching in Conversation ... of Code Switching for Overlap Resolution journal Research on Language and Social Interaction volume 34 number 4 pages 421 51 ref Analyst Peter Auer suggests that code switching does not simply reflect ... more details
refimprove date March 2010 Bank switching is a technique to increase the amount of usable memory beyond ... modern microcontroller s and microprocessor s use bank switching to manage random access memory ... s. The technique was common in 8 bit microcomputer systems. Bank switching may also be used to work ... switching can be considered a way of extending the address bus of a processor with some external register .... Several bank switching control bits could be gathered into a register, approximately doubling ... switching operation to access large memory objects. Generally a bank switching system will have one ... memory scheme, bank switching must be explicitly managed by the running program or operating system ... of data, and then call the bank switching routine to make that bank active. ref name Mueller92 Scott ... 700 ref However, bank switching can access data much faster than, for example, retrieving the data ... 64 kb can be accessed at any time by the processor. The operating system must manage the bank switching .... Bank switching allowed extra memory and functions to be added to a computer design without the expense and incompatibility of switching to a processor with a wider address bus . For example, the Commodore 64 C64 used bank switching to allow for a full 64KB of RAM and still provide for ROM and memory ... switching technique that allows more than the 640 KB of RAM defined by the original IBM PC architecture ... bank switching for memory above 1 MB called extended memory , which is not directly addressable ... way it works like the bank switching of EMS, from the perspective of a program that uses it. Later ... emulates XMS also, for those programs that require it. Video game consoles Bank switching was also ... of ROM, so later 2600 game cartridge electronics cartridge s contained their own bank switching hardware ..., addressed via bank switching called a Multi Memory Controller . Game Boy cartridges used a chip called MBC Memory Bank Controller , which not only offered ROM bank switching, but also cartridge SRAM ... more details
Distributed switching is an architecture in which multiple central processing unit processor controlled switching units are distributed. There is often a hierarchy of switching elements, with a centralized Server computing host Stored Program Control exchange switch and with remote switches located close to concentrations of users. Use in telephony networks Distributed switching is often used in telephony networks, though it is often called host remote switching . In rural areas, population centers tend to be too small for economical deployment of a full featured dedicated switch, and distances between these centers make transmission telecommunications transmission costs relatively high. Normal telephone traffic patterns show that most calling is done between people in a community of interest , in this case a geographical one the population center. Use of distributed switching allows for the majority of calls that are local to that population center to be switched there without needing to be transported to and from the host switch. The host switch provides connectivity between the remote switches and to the larger network, and the host may also directly handle some rare and complex call types conference call ing, for example that the remote itself is not equipped to handle. Host switches also perform OAM&P Operation, Administration, Maintenance, and Provisioning functions, including billing, for the entire cluster of the host and its remote switches. A key capability of a remote switch is the ability to act in emergency standalone ESA mode, wherein local calls can still be placed even in the event that the connection between that remote and the host has been lost. In this mode, only local calling is available anyway, so the billing capability of the host switch is not required ... utilize distributed switching on separate cards within an equipment chassis . Even when this is used, it is common to have a centralized switching fabric to interconnect the distributed switches. This architecture ... more details
Unreferenced date September 2009 A Switching loop or Bridge loop occurs in computer network s when there is more than one Layer 2 OSI model path between two endpoints e.g. multiple connections between two network switch es or two ports on the same switch connected to each other . The loop creates broadcast radiation as broadcasts and multicast s are forwarded by switches out every Computer port hardware port , the switch or switches will repeatedly rebroadcast the broadcast messages flooding the network. Since the Layer 2 header does not support a time to live TTL value, if a frame is sent into a looped topology, it can loop forever. A physical topology that contains switching or bridge loop is necessary for reliability, yet a switched network must not have loops. The solution is to allow physical loops, but create a loop free logical topology using the spanning tree protocol STP on the switches. Broadcasts In the case of broadcast packets broadcast radiation over a switching loop, the situation may develop into a broadcast storm . MAC database instability Switching loops can cause misleading entries in a switch s Media Access Control MAC database and can cause endless unicast call stack frames to be broadcast throughout the network. In a redundant switched network it is possible for switches to learn the wrong information. A switch can incorrectly learn that a MAC address is on one port, when it is actually on a different port. Multiple frame transmissions In a redundant switched network it is possible for an end device to receive the same frame multiple times. Misinterpretations It is not true that within a switching loop packets will circulate the network until their time to live TTL value expires as no TTL concept exists at Layer 2 . DEFAULTSORT Switching Loop Category Network performance Category Network topology compu network stub ... more details
Infobox film name Switching Channels image Switching Channels.jpg image size 200px caption Theatrical release poster director Ted Kotcheff producer Martin Ransohoff writer Jonathan Reynolds br Play br Ben Hecht br Charles MacArthur narrator starring Kathleen Turner br Burt Reynolds br Christopher Reeve music Michel Legrand cinematography Fran ois Protat editing Thom Noble studio Switching Channels Inc. distributor TriStar Pictures released start date 1988 3 4 runtime 105 minutes country United States language English budget gross preceded by followed by Switching Channels is a 1988 American comedy film remake of The Front Page also more famously remade as His Girl Friday in 1940 . It stars Kathleen Turner as Christy Colleran, Burt Reynolds as John L. Sullivan IV, Christopher Reeve as Blaine Bingham, Ned Beatty as Roy Ridnitz, Henry Gibson as Ike Roscoe, and George Newbern as Sigenthaler. The film was notorious for its harsh infighting between Reynolds and Turner during filming, and the film was seen as a failure, commercially and critically. It is available on DVD in DVD region code Regions 2 and 4. Plot The film uses only the basic premise of The Front Page and His Girl Friday . All ... Gray Lady Down . Filmed primarily in Canada with a Canadian director Ted Kotcheff , Switching Channels ... TV series Siskel & Ebert gave Switching Channels mixed results Roger Ebert Ebert was positive about ... in the film and gave Switching Channels a thumbs down. ref cite web title Switching Channels ... bventertainment.go.com tv buenavista ebertandroeper index2.html ?sec 6&subsec switching channels accessdate May 9, 2009 ref Rotten Tomatoes currently lists Switching Channels with a 56 rating. ref cite web title Switching Channels movie reviews publisher Rotten Tomatoes url http www.rottentomatoes.com m switching channels accessdate May 9, 2009 ref Christopher Reeve, who played against type as the hapless .... External links imdb title id 0096203 title Switching Channels Amg movie 48201 Switching Channels ... more details
For a frequency synthesizer , the switching time or more colloquially the switching speed is the amount of time from when the command for the next frequency is requested until the time that the synthesizer s output becomes usable and meets the specified requirements. Such requirements will vary depending on the design of the synthesizer. In the 1970s switching speeds ranged from 1 milli sec to 10 micro seconds. A more general statement has been given by James A. Crawford 50 reference cycles as a general rule of thumb. By this rule, a reference frequency of 50 kHz has a settling time of 1 milli seconds. ref Craw1994 Crawford, 1994, p. 303 ref Two other authors state Hamid Rategh and Thomas H. Lee engineering professor Thomas H. Lee that the switching time i.e., settling time is a function of the percentage change in the feedback division ratio. ref Rategh2001 Rategh, 2001, p. 25 ref So according to them, the delta N over N itself determines the switching time, where N is the frequency synthesizer s feedback divisor. References Reflist Further reading cite id Craw1994 Crawford, James A. 1994. Frequency Synthesizer Design Handbook , Artech House, ISBN 0 89006 440 7 cite cite id Rategh2001 Rategh, Hamid and R. Lee, Thomas H. Stanford University 2001. Multi GHz Frequency Synthesis & Division Frequency Synthesizer Design for 5 GHz Wireless LAN Systems , Kluwer, ISBN 0 7923 7533 5 cite Category Oscillators Engineering stub ... more details
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