Specifications
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WMM Parameters (for advanced users) 
AIFs (Arbitrary 
Inter-Frame 
Space) 
Arbitrary Inter-Frame Space is the minimum wait 
time interval between the wireless medium 
becoming idle and the start of transmission of a 
frame over the network. 
Cwmin 
(Contention 
Window 
Minimum) 
Contention Window Minimum is the minimum 
random wait time drawn from this interval or 
window for the backoff mechanism on the network. 
CwMax 
(Contention 
Window 
Maximum) 
Contention Window Maximum is the maximum 
random wait time drawn from this interval or 
window for the backoff mechanism on the network. 
TxOp limit 
(Transmit 
Opportunity 
Limit) 
Transmit Opportunity limit specifies the minimum 
duration that an end-user device can transmit data 
traffic after obtaining a transmit opportunity. TxOp 
limit can be used to give data traffic longer and 
shorter access. 
NoAck (No 
Acknowledgeme
nt) 
No Acknowledgement provides control of the 
reliability of traffic flow. Usually an acknowledge 
packet is returned for every packet received, 
increasing traffic load and decreasing 
performance. 
Enabling No Acknowledgement cancels the 
acknowledgement. This is useful for data traffic 
where speed of transmission is important. 
ACM (Admission 
Control 
Mandatory) 
Admission Control Mandatory enables WMM on the 
radio interface. When ACM is enabled, associated 
clients must complete the WMM admission control 
procedure before access. 
BE (Best Effort) 
Parameters for Data0 Best Effort. 
Best Effort data traffic has no prioritization and 
applications equally share available bandwidth. 
BK (Background) 
Parameters for Data1 Background. 
Background data traffic is de-prioritized and is 
mostly for backup applications, or background 
transfers like backup applications or background 
transfers like bulk copies that do not impact 
ongoing traffic like Internet downloads. 
VI (Video) 
Parameters for video data traffic. 
VO (Voice)  Parameters for voice data traffic. 










