TRENDnet 12dBi User Manual page 33

TRENDnet User's Guide
minimum transmission delay for Voice, Video, multimedia, and mission critical
applications, and rely on best-effort parameters for traditional IP data.
As an Example, time-sensitive Voice & Video, and multimedia are given
effectively higher priority for transmission (lower wait times for channel
access), while other applications and traditional IP data which are less time-
sensitive but often more data-intensive are expected to tolerate longer wait
times.
Aifsn : The Arbitration Inter-Frame Spacing Number specifies a wait time

(in milliseconds) for data frames
CWmin : Minimum Contention Window. This parameter is input to the

algorithm that determines the initial random backoff wait time
("window") for retry of a transmission. The value specified here in the
Minimum Contention Window is the upper limit (in milliseconds) of a
range from which the initial random backoff wait time is determined.
CWmax : Maximum Contention Window. The value specified here in the

Maximum Contention Window 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".
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.
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.
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
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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.
Data Transmitted
Priority
Queue Clients to AP
AC_BK Background. Low
AC_BE Best Effort Medium
AC_VI Video High
AC_VO Voice High
WMM Parameters of Station : This affects traffic flowing from the client

station to the access point.
Aifsn : The Arbitration Inter-Frame Spacing Number specifies a wait time

(in milliseconds) for data frames
CWmin : Minimum Contention Window. This parameter is input to the algorithm that
determines the initial random backoff wait time ("window") for retry of a transmission.
The value specified here in the Minimum Contention Window is the upper limit (in
milliseconds) of a range from which the initial random backoff wait time is determined.
CWmax : Maximum Contention Window. The value specified here in the Maximum
Contention Window 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".
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
TEW-676APBO
Description
High throughput. Bulk data that requires
maximum throughput and is not time-sensitive is
sent to this queue (FTP data, for example).
Medium throughput and delay. Most traditional
IP data is sent to this queue
Minimum delay. Time-sensitive video data is
automatically sent to this queue
Time-sensitive data like VoIP and streaming
media are automatically sent to this queue
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