Delivery traffic indication message

A delivery traffic indication map is a kind of traffic indication map (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 multicast/broadcast data on the channel following the normal channel access rules (CSMA/CA). This helps to have minimum collision and in effect, increased throughput. In cases where there is not much interference, or where the number of clients is limited, the DTIM interval has little or no significance. Usually a value of 1 or 2. Also see Wi-Fi as established by the Wi-Fi Alliance.