Cerio OW-200N2, User Manual

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User’s Manual
500mW eXtreme Power 11Na Outdoor Bridge
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is the upper limit (in milliseconds) for the doubling of the random backoff value. This doubling continues
until either the data frame is sent or the Maximum Contention Window size is reached. Once the
Maximum Contention Window size is reached, retries will continue until a maximum number of retries
allowed is reached. Valid values for the "cwmax" are 1, 3, 7, 15, 31, 63, 127, 255, 511, or 1024. The
value for "cwmax" must be higher than the value for "cwmin".
9
Txop : Transmission Opportunity is an interval of time when a WME AP has the right to initiate
transmissions onto the wireless medium (WM). This value specifies (in milliseconds) the Transmission
Opportunity (TXOP) for AP; that is, the interval of time when the WMM AP has the right to initiate
transmissions on the wireless network.
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ACM : Admission Control Mandatory, ACM only takes effect on AC_VI and AC_VO. When you do not
click Checkbox, it means that the ACM is controlled by the connecting AP. If you click Checkbox, it
means that the Client is in charge.
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AckPolicy : Acknowledgment Policy, WMM defines two ACK policies: Normal ACK and No ACK . Click
“ Checkbox ” indicates “ No ACK ”
When the no acknowledgment (No ACK) policy is used, the recipient does not acknowledge received
packets during wireless packet exchange. This policy is suitable in the environment where
communication quality is fine and interference is weak. While the No ACK policy helps improve
transmission efficiency, it can cause increased packet loss when communication quality deteriorates.
This is because when this policy is used, a sender does not retransmit packets that have not been
received by the recipient.
When the Normal ACK policy is used, the recipient acknowledges each received unicast packet.
Î
WMM Parameters of Station : This affects traffic flowing from the client station to the access point.
Queue
Data Transmitted
Clients to AP
Priority Description
AC_BK Background. Low
High throughput. Bulk data that requires maximum throughput and is not
time-sensitive is sent to this queue (FTP data, for example).