Cisco Cisco WAP351 Wireless-N Dual Radio Access Point with 5-Port Switch 관리 매뉴얼

다운로드
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Wireless
Quality of Service
Cisco WAP131 and WAP351 Administration Guide
110
5
Optimized for Voice—Populates the WAP device and the Station EDCA 
parameters with values that are best for voice traffic.
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  4
Configure the following EDCA and Station EDCA parameters:
NOTE
These parameters are configurable only if you choose 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 1024. 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.