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CSMA/CD Medium Access Control (MAC)

This defines how computers using Ethernet can share a common medium: Carrier Sense, Multiple Access, with Collision Detection.
 
Multiple Access
all computers have equal access: there are no masters or slaves, etc. If the shared channel is clear, a computer may begin to transmit immediately.
 
Carrier Sense
if the channel is busy, continue to listen, and attempt to transmit as soon as it becomes available.
 
Collision Detection
if a collision is detected (ie, another computer started to transmit at the same time), immediately cease transmission. Wait a random period of time, then start all over.

 


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