Black Box LW0050A, Руководство пользователя

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APPENDIX E: IEEE 802.11 Technical Tutorial
ToDS
This bit is set to 1 when the frame is addressed to the Access Point for forwarding
to the Distribution System (including the case where the destination station is in
the same BSS, and the Access Point is to relay the frame).
The Bit is set to 0 in all other frames.
FromDS
This bit is set to 1 when the frame is received from the Distribution System.
More Fragments
This bit is set to 1 when there are more fragments belonging to the same frame
following the current fragment.
Retry
This bit indicates that this fragment is a retransmission of a previously transmitted
fragment. This is used by the receiver station to recognize duplicate transmissions
of frames that may occur when an Acknowledgment packet is lost.
Power Management
This bit indicates the Power Management mode that the station will be in after the
transmission of this frame. This is used by stations which are changing state either
from Power Save to Active or vice versa.
More Data
This bit is used for Power Management as well as by the Access Point to indicate
that there are more frames buffered for this station. The station may decide to use
this information to continue polling or even changing to Active mode.
WEP
This bit indicates that the frame body is encrypted according to the WEP algorithm
Order
This bit indicates that this frame is being sent using the Strictly-Ordered service
class. (The Strictly-Ordered Service Class is defined for users that cannot accept
change of ordering between Unicast Frames and Multicast Frames—ordering of
Unicast frames to a specific address is always maintained. The only known protocol
that would need this service class is DEC LAT.)