Command Line Interface
7-132
7
interpretability with other wired network QoS policies. While the four ACs
are specified for specific types of traffic, WMM allows the priority levels to
be configured to match any network-wide QoS policy. WMM also specifies
a protocol that access points can use to communicate the configured traffic
priority levels to QoS-enabled wireless clients.
• Although turning off the requirement for the sender to wait for an
acknowledgement can increases data throughput, it can also result in a
high number of errors when traffic levels are heavy.
Example
wmmparam
This command configures detailed WMM parameters that apply to the access point
(AP) or the wireless clients (BSS).
Syntax
wmmparam <AP | BSS> <ac_number> <LogCwMin> <LogCwMax> <AIFS>
<TxOpLimit> <admission_control>
•AP - Access Point
•BSS - Wireless client
•ac_number - Access categories (ACs) – voice, video, best effort, and
background. These categories correspond to traffic priority levels and are
mapped to IEEE 802.1D priority tags as shown in Table 6-1. (Range: 0-3)
•LogCwMin - Minimum log value of the contention window. This is the initial
upper limit of the random backoff wait time before wireless medium access
can be attempted. The initial wait time is a random value between zero and
the LogCwMin value. Specify the LogCwMin value. Note that the LogCwMin
value must be equal or less than the LogCwMax value.
(Range: 1-15 microseconds)
•LogCwMax - Maximum log value of the contention window. This is the
maximum upper limit of the random backoff wait time before wireless
medium access can be attempted. The contention window is doubled after
each detected collision up to the LogCwMax value. Note that the CWMax
value must be greater or equal to the LogCwMin value.
(Range: 1-15 microseconds)
•AIFS - Arbitrary InterFrame Space specifies the minimum amount of wait
time before the next data transmission attempt.
(Range: 1-15 microseconds)
•TXOPLimit - Transmission Opportunity Limit specifies the maximum time
an AC transmit queue has access to the wireless medium . When an AC
queue is granted a transmit opportunity, it can transmit data for a time up to
the TxOpLimit. This data bursting greatly improves the efficiency for high
data-rate traffic. (Range: 0-65535 microseconds)
Enterprise AP(if-wireless a)#wmm-acknowledge-policy 0 noack
Enterprise AP(if-wireless a)#