CSMA/CA

In short: CSMA/CA (carrier sense multiple access with collision avoidance) is the access method in Wi-Fi. Collisions are avoided instead of detected.

In more detail: Radio devices cannot send and listen at the same time. Therefore a device listens, waits a random time (backoff) and then sends. The receiver confirms with an ACK.

In Depth

RTS/CTS

Optionally the sender asks with RTS, the receiver answers with CTS. Other devices stay quiet (helps with the “hidden node” problem).

Comparison

CSMA/CD belongs to classic Ethernet. See WLAN, wireless, ACK.

See also: CSMA/CD, Wi-Fi (WLAN), Wireless, ACK