Cisco Cisco WAP371 Wireless-AC N Access Point with Single Point Setup Manuel De Maintenance

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Wireless
Quality of Service
Cisco Small Business WAP371 Wireless Access Point Administration Guide 
92
5
Custom—Enables you to choose custom EDCA parameters.
These four queues are defined for different types of data transmitted from WAP-to-station. If 
you choose a Custom template, the parameters that define the queues are configurable; 
otherwise, they are set to predefined values appropriate to your selection. The four queues are:
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).
STEP  3
Configure the following EDCA and Station EDCA parameters:
NOTE
These parameters are configurable only if you selected Custom in the previous 
step.
Arbitration Inter-Frame Space—A wait time for data frames. The wait time is measured 
in slots. Valid values for AIFS are 1 through 255.
Minimum Contention Window—An input to the algorithm that determines the initial 
random backoff wait time (window) for retry of a transmission. 
This value is the upper limit (in milliseconds) of a range from which the initial random 
backoff wait time is determined.
The first random number generated is 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 backoff value reaches the number defined in the Maximum 
Contention Window.
Valid values are 1, 3, 7, 15, 31, 63, 127, 255, 511, or 1023. This value must be lower 
than the value for the Maximum Contention Window.
Maximum Contention Window—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.