Allied Telesis AT-WA7400/EU - Manual (Page 169)

AT-WA7400 Management Software User’s Guide
169
Configuring
Station EDCA
Parameters
Station Enhanced Distributed Channel Access (EDCA) parameters affect
traffic flowing from the client station to the access point. To configure the
EDCA parameters, perform the following procedure:
1. In the Station EDCA parameters section of the Quality of Service page,
configure the following parameters:
Queue
Queues are defined for different types of data transmitted from station-
to-access point:
Data 0 (Voice) - Highest priority queue, minimum delay. Time-sensitive
data such as VoIP and streaming media are automatically sent to this
queue.
Data 1(Video) - Highest 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 160.
AIFs
(Inter-Frame Space)
The Arbitration Inter-Frame Spacing (AIFs) specifies a wait time (in
milliseconds) for data frames.
For more information, see “EDCF Control of Data Frames and
Arbitration Interframe Spaces” on page 162.
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.
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 continues until the size of the random