CSMA

CSMA/CD 1 'Carrier Sense Multiple Access With Collision Detection' ('CSMA/CD') is a media access control method used most notably in local area networking using early Ethernet technology

CSMA/CD 1 CSMA/CD is a modification of pure carrier sense multiple access (CSMA). CSMA/CD is used to improve CSMA performance by terminating transmission as soon as a collision is detected, thus shortening the time required before a retry can be attempted.

CSMA/CD - Applications 1 IEEE Std 802.3, which defines all Ethernet variants, for historical reasons still bears the title Carrier sense multiple access with collision detection (CSMA/CD) access method and physical layer specifications.

GraphicsMagick 1 'GraphicsMagick' is a fork (software development)|fork of ImageMagick, emphasizing stability of both programming API and command-line options. It was branched off ImageMagick's version in 2002 after irreconcilable differences emerged in the developers' group.[ developerm= w=2 imagemagick-developer mailing list: Introducing GraphicsMagick Project, 15 March 2003]

GraphicsMagick 1 In addition to the programming language APIs available with ImageMagick, GraphicsMagick also includes a Tcl API, called TclMagick.

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CSMA CA 1 'Carrier sense multiple access with collision avoidance' ('CSMA/CA') in computer networking, is a network multiple access method in which Carrier wave|carrier sensing is used, but Node (networking)|nodes attempt to avoid collisions by transmitting only when the channel is sensed to be idle. When they do transmit, nodes transmit their packet data in its entirety.

CSMA CA 1 It is particularly important for wireless networks, where the collision detection of the alternative Carrier sense multiple access with collision detection|CSMA/CD is unreliable due to the hidden node problem.

CSMA CA - Details 1 Collision avoidance is used to improve the performance of the CSMA method by attempting to divide the channel somewhat equally among all transmitting nodes within the collision domain.

CSMA CA - Details 1 Unlike CSMA/CD, it is very challenging for a wireless node to listen at the same time as it transmits (its transmission will dwarf any attempt to listen)

CSMA CA - Details 1 Although CSMA/CA has been used in a variety of wired communication systems, it is particularly beneficial in a wireless LAN due to a common problem of multiple stations being able to see the Access Point, but not each other

CSMA CA - Performance 1 Studies show that under ideal propagation conditions (simulations), direct-sequence spread spectrum|Direct Sequence Spread Spectrum (DSSS) provides the highest throughput for all nodes on a network when used in conjunction with CSMA/CA and the IEEE RTS/CTS exchange under light network load conditions

CSMA CA - Usage 1 * Apple Computer|Apple's LocalTalk implemented 'CSMA/CA' on an electrical bus using a three-byte jamming signal.

CSMA CA - Usage 1 * The ITU-T G.hn standard, which provides a way to create a high-speed (up to 1 Gigabit/s) local area network using existing home wiring (Power line communication|power lines, phone lines and ethernet over coax|coaxial cables), uses CSMA/CA as a channel access method for flows that don't require guaranteed quality of service, specifically the CSMA/CARP variant.

Carrier sense multiple access - CSMA with collision avoidance 1 In CSMA/CA collision avoidance is used to improve the performance of CSMA by attempting to be less greedy on the channel. If the channel is sensed busy before transmission then the transmission is deferred for a random interval. This reduces the probability of collisions on the channel.

Carrier sense multiple access - Virtual time CSMA 1 VTCSMA is designed to avoid collision generated by nodes transmitting signals simultaneously, used mostly in hard Real- time computing|real-time systems. The VTCSMA uses two clocks at every node, a virtual clock (vc) and a real clock (rc) which tells real time. When the channel is sensed to be busy, the vc freezes, when channel is free, it is reset. Hence, calculating vc runs faster than rc when channel is free, and vc is not initiated when channel is busy.

Carrier sense multiple access - CSMA access modes 1 1-persistent CSMA is used in CSMA/CD systems including Ethernet.

Carrier sense multiple access - CSMA access modes 1 ; Non-persistent : Non persistent CSMA is a non aggressive transmission algorithm

Carrier sense multiple access - CSMA access modes 1 p-persistent CSMA is used in CSMA/CA systems including Wi-Fi and other packet radio systems.

Carrier sense multiple access - CSMA access modes 1 O-persistent CSMA is used by CobraNet, LonWorks and the controller area network.

CSMA/CARP 1 Again, CSMA/CARP is similar to the functions of the CSMA/CA

CSMA/CARP 1 In addition to having a different IFS per priority, a station in a CSMA/CARP network will add a random backoff to its waiting period, to reduce the collision probability between stations that have to transmit packets in the same priority.

CSMA/CARP - Applications 1 * The ITU-T G.hn standard, which provides high-speed local area networking over existing home wiring (power lines, phone lines and coaxial cables) includes support for CSMA/CARP, although only during certain periods of time called Shared Transmission Opportunities (STXOP). During the rest of the time, G.hn uses a Time division multiple access Channel access method to ensure Quality of Service.

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