CSMA/CA

Carrier Sense Multiple Access/Collision Avoidance is a network contention protocol that listens to a network in order to avoid collisions, unlike CSMA/CD that deals with network transmissions once collisions have been detected, CSMA/CA contributes to network traffic before any real data is transmitted, it has to broadcast a signal onto the network in order to listen for collision scenarios and to tell other devices not to broadcast.