D-Link DWL-8500AP, Руководство администратора

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D-Link Unified Access Point Administrator’s Guide
Table 22.
QoS Settings
Field Description
AP EDCA Parameters
Queue Queues are defined for different types of data transmitted from AP-to-
station:
• Data 0 (Voice)—High priority queue, minimum delay. Time-
sensitive data such as VoIP and streaming media are automatically
sent to this queue.
• Data 1(Video)—High priority queue, minimum delay. Time-
sensitive video data is automatically sent to this queue.
• Data 2 (best effort)—Medium priority queue, medium throughput
and delay. Most traditional IP data is sent to this queue.
• Data 3 (Background)—Lowest priority queue, high throughput.
Bulk data that requires maximum throughput and is not time-
sensitive is sent to this queue (FTP data, for example).
For more information, see “QoS Queues and Parameters to Coordinate
Traffic Flow” on page 70.
AIFS
(Inter-Frame Space)
The Arbitration Inter-Frame Spacing (AIFS) specifies a wait time (in
milliseconds) for data frames.
Valid values for AIFS are 1 through 255.
For more information, see “EDCF Control of Data Frames and
Arbitration Interframe Spaces” on page 71.
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 for Minimum Contention Window is the upper limit
(in milliseconds) of a range from which the initial random backoff wait
time is determined.
The first random number generated will be a number between 0 and the
number specified here.
If the first random backoff wait time expires before the data frame is
sent, a retry counter is incremented and the random backoff value
(window) is doubled. Doubling will continue until the size of the
random backoff value reaches the number defined in the Maximum
Contention Window.
Valid values for cwMin are 1, 3, 7, 15, 31, 63, 127, 255, 511, or 1023.
The value for cwMin can be equal to or lower than the value for cwMax.
For more information, see “Random Backoff and Minimum / Maximum
Contention Windows” on page 72.