136:. To avoid collisions, a carrier sensing mechanism is used. Here each computer listens to the network before attempting to transmit. If the network is busy, it waits until network quiets down. In carrier detection, computers continue to listen to the network as they transmit. If computer detects another signal that interferes with the signal it is sending, it stops transmitting. Both computers then wait for a random amount of time and attempt to transmit. Contention methods are most popular media access control method on LANs.
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An alternative method to handle collisions in a contention-based system is to attempt to avoid them. Some systems may utilize a strict scheduling guideline to identify who may use which resources when. Other systems may have the senders listen to the channel immediately prior to transmitting and
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applies specifically to the number of people connected to an ISP who share a set amount of bandwidth. Typical values would be 50:1 for home users (that is to say that 50 people or lines will vie for the same bandwidth) and 20:1 for business users. It is for this reason that the shortfall between
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For recovery, some systems simply cause senders to re-transmit collided data (perhaps with backing-off algorithms which reduce the sender's re-transmit rate when collisions keep occurring) or use Error
Correction techniques such as
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A collision can be detected by listening to the shared medium immediately after transmitting and identifying collision characteristics ; or by capturing data from the medium and performing error detection.
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supplier-claimed access speeds and those experienced by the consumer once signed-up to a contract is particularly bad at just those times when most consumers actually want to use the service.
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is a media access method that is used to share a broadcast medium. In contention, any computer in the network can transmit data at any time (first come-first served).
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One method to handle collisions in a contention based system is to optimize collision detection and subsequent recovery.
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This system breaks down when two computers attempt to transmit at the same time. This is known as a
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Collisions are a condition that arises when two or more
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291:Paul Goransson; Raymond Greenlaw (2007).
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109:Learn how and when to remove this message
215:Multiple Access with Collision Avoidance
190:communication link. A contention-based
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166:determine suitable times to transmit.
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123:statistical time division multiplexing
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58:"Contention" telecommunications
47:adding citations to reliable sources
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295:Secure Roaming in 802.11 Networks
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140:Collision detection and recovery
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360:media access control
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584:Collision avoidance
161:Collision avoidance
546:Collision recovery
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32:This article
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537:Packet-based
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245:. The term
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99:January 2009
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41:Please help
36:verification
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303:. pp.
188:half duplex
728:Categories
645:Token Ring
278:References
196:collisions
127:contention
69:newspapers
650:Token bus
627:CSMA/CARP
134:collision
655:MS-ALOHA
460:TD-SCDMA
266:See also
239:facility
607:CSMA/CA
574:CSMA/CD
564:R-ALOHA
493:HC-SDMA
475:MC-CDMA
470:FH-CDMA
465:DS-CDMA
455:TD-CDMA
427:MF-TDMA
395:SC-FDMA
184:channel
83:scholar
450:W-CDMA
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301:Newnes
235:system
211:(CSMA)
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676:VANET
671:MANET
597:MACAW
569:AX.25
554:ALOHA
432:STDMA
390:OFDMA
90:JSTOR
76:books
602:CSMA
592:MACA
518:PAMA
503:PDMA
485:SDMA
442:CDMA
419:TDMA
407:WDMA
377:FDMA
358:and
309:ISBN
202:The
180:time
176:data
62:news
713:FDD
708:TDD
681:DTN
622:HCF
617:PCF
612:DCF
402:WDM
385:FDM
225:In
154:FEC
121:In
45:by
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