Data Transfer
The barter of abstracts in an 802.11 arrangement is bidirectional amid the radio agenda and access
point. As mentioned earlier, abstracts frames in an basement wireless LAN do not biking directly
between wireless users. Instead, the admission point relays the data.
A radio agenda or admission point (802.11 station) accepting the destination MAC abode of the abstracts frame
replies with an accepting (ACK) frame. This adds cogent aerial to a wireless LAN
as compared to an Ethernet arrangement that does not crave ACKs for every abstracts frame. The ACKs are
necessary with 802.11 due to the attributes of the aggregate radio medium; abstracts accident is abundant added likely
with the wireless medium, so wireless LANs accomplish absurdity apprehension and absurdity alteration at Layer 2.
If an 802.11 base sending a abstracts anatomy does not accept an ACK afterwards a specific aeon of time,
the base retransmits the frame. These retransmissions action up to a accurate limit, which is
generally three to seven times. Afterwards that, higher-layer protocols, such as Manual Control
Protocol (TCP), charge accommodate absurdity recovery.
To acquiesce for continued range, 802.11 includes automated abstracts amount shifting. For example, an
802.11 base about lowers its manual abstracts amount if a retransmission is necessary. Access
points abutment assorted abstracts ante to facilitate this affectionate of operation, area altered remote
stations ability address abstracts upstream at altered rates.