Back وصول متعدد باستشعار الحامل Arabic CSMA Catalan CSMA Czech CSMA Danish Carrier Sense Multiple Access German Carrier sense multiple access Spanish CSMA Basque CSMA French CSMA HE CSMA Italian
Carrier-sense multiple access (CSMA) is a medium access control (MAC) protocol in which a node verifies the absence of other traffic before transmitting on a shared transmission medium, such as an electrical bus or a band of the electromagnetic spectrum.
Under CSMA, a transmitter uses a carrier-sense mechanism to determine whether another transmission is in progress before initiating a transmission. That is, it tries to detect the presence of a carrier signal from another node before attempting to transmit. If a carrier is sensed, the node waits for the transmission in progress to end before initiating its own transmission. Using CSMA, multiple nodes may, in turn, send and receive on the same medium. Transmissions by one node are generally received by all other nodes connected to the medium.
Variations on basic CSMA include addition of collision-avoidance (CSMA/CA), collision-detection (CSMA/CD) and collision-resolution techniques.