Delivery traffic indication message

A delivery traffic indication message is a kind of traffic indication message (TIM) which informs the clients about the presence of buffered multicast/broadcast data on the access point. It is generated within the periodic beacon at a frequency specified by the DTIM Interval. Beacons are packets sent by an access point to synchronize a wireless network. Normal TIMs that are present in every beacon are for signaling the presence of buffered unicast data. After a DTIM, the access point will send the multicasted/broadcasted data on the channel following the normal channel access rules (CSMA/CA). Also see Wi-Fi as established by the Wi-Fi Alliance