Wireless is a half-duplex medium. Unlike Ethernet, wireless devices must contend for air time to transmit their frames. To avoid collisions, there are a number of mechanisms used:

* Physical Carrier Sense
* Virtual Carrier Sense
* a Coordination Function

In this episode, I go over these mechanisms and describe their purpose.
Here is a screenshot of a wireless frame showing the Duration value within the header. This Duration value is used to set a device’s NAV timer.

Links and Resources

* 802.11 Arbitration