Frame Types - Alvarion BreezeNET PRO.11 Series User Manual

As part of its Beacon Frames, the AP also periodically transmits information about
which Power Saving Stations have frames buffered at the AP, so these stations
wake up in order to receive the Beacon Frame. If there is an indication that there is
a frame stored at the AP waiting for delivery, then the station stays awake and
sends a Polling message to the AP to get these frames.
Multicasts and Broadcasts are stored by the AP, and transmitted by the AP at pre-
defined intervals (called DTIM), all stations - both stations working in Power
Saving mode and stations working in Normal mode, will be awake at that period
and will receive this kind of frames.
Unicasts are stored by the AP, and transmitted at station-defined intervals (called
Listen Intervals), when all stations who wish to receive this kind of frames are
awake. Unicast frames are transmitted upon request only, whereas, Multicast
frames are transmitted automatically at every DTIM interval.
Note:

9.5.8 Frame Types

There are three main types of frames:
Data Frames: which are used for data transmission
Control Frames: which are used to control access to the medium (e.g. RTS,
CTS, and ACK), and
Management Frames: which are frames that are transmitted in the same
manner as data frames to exchange management information, but are not
forwarded to upper layers (e.g. beacon frames).
Each frame type is subdivided into different Subtypes, according to its specific
function.
BreezeNET PRO.11
Unicast frames can be also poled by the stations at the DTIM intervals.
9-37
Appendix
User's
Guide