wmm edca-client (SSID profile view)

Function

The wmm edca-client command configures EDCA parameters for STAs.

The undo wmm edca-client command restores the default EDCA parameter settings of STAs.

Table 1 lists the default EDCA parameter settings for STAs.

**Table 1** Default EDCA parameter settings for STAs
Packet Type	ECWmax	ECWmin	AIFSN	TXOPLimit
AC_VO	3	2	2	47
AC_VI	4	3	2	94
AC_BE	10	4	3	0
AC_BK	10	4	7	0

Format

wmm edca-client { ac-vo | ac-vi | ac-be | ac-bk } { aifsn aifsn-value | ecw ecwmin ecwmin-value ecwmax ecwmax-value | txoplimit txoplimit-value } ^*

undo wmm edca-client

Parameters

Parameter	Description	Value
ac-vo	Indicates AC_VO packets.	-
ac-vi	Indicates AC_VI packets.	-
ac-be	Indicates AC_BE packets.	-
ac-bk	Indicates AC_BK packets.	-
aifsn aifsn-value	Specifies the arbitration inter frame spacing number (AIFSN), which determines the channel idle time.	The value is an integer that ranges from 2 to 15.
ecwmin ecwmin-value	Specifies the exponent form of the minimum contention window. ecwmin-value and ecwmax-value determine the average backoff time.	The value is an integer that ranges from 0 to 15 and must be less than or equal to the ecwmax-value value.
ecwmax ecwmax-value	Specifies the exponent form of the maximum contention window. ecwmin-value and ecwmax-value determine the average backoff time.	The value is an integer that ranges from 0 to 15 and must be greater than or equal to the ecwmin-value value.
txoplimit txoplimit-value	Specifies the transmission opportunity limit (TXOPLimit), which determines the maximum duration in which a STA can occupy a channel. A larger TXOPLimit value indicates a longer duration to occupy a channel.	The value is an integer that ranges from 0 to 255. The unit is 32 microseconds. NOTE: If the TXOPLimit value is 0, the STA can send only one data frame every time it occupies a channel.

Views

SSID profile view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

WMM classifies data packets into the following access categories (ACs): AC_VO, AC_VI, AC_BE, and AC_BK. A set of EDCA parameters is set for each AC queue. These parameters determine the capabilities of a queue to occupy a channel. You can set EDCA parameters for packets of different ACs to provide differentiated priorities to the packets and different capabilities to compete for channels. In this way, differentiated services are implemented.

Table 2 describes the EDCA parameters.

**Table 2** EDCA parameter description
Parameter	Meaning
Arbitration Interframe Spacing Number (AIFSN)	The DIFS has a fixed value. WMM provides different DIFS values for different ACs. A large AIFSN value means that the STA must wait for a long time and has a low priority.
Exponent form of CWmin (ECWmin) and exponent form of CWmax (ECWmax)	ECWmin specifies the minimum backoff time, and ECWmax specifies the maximum backoff time. Together, they determine the average backoff time. Large ECWmin and ECWmax values mean a long average backoff time for the STA and a low STA priority.
Transmission Opportunity Limit (TXOPLimit)	After preempting a channel, the STA can occupy the channel within the period of TXOPLimit. A large TXOPLimit value means that the STA can occupy the channel for a long time. If the TXOPLimit value is 0, the STA can only send one data frame every time it preempts a channel.

Precautions

The EDCA parameters configured for the four AC queues take effect only after the WMM function is enabled using the undo wmm disable command.
By default, queues of AC_VO, AC_VI, AC_BE, and AC_BK are in descending order of priority. Priorities of the four queues are determined by their EDCA parameters.

EDCA parameters must be configured properly. The scenarios for the reference EDCA parameter settings and ACK policies are as follows:

Table 3 lists the reference EDCA parameter settings and ACK policies for APs in voice scenarios.

**Table 3** Reference EDCA parameter settings and ACK policies for APs in voice scenarios
Packet Type	ECWmax	ECWmin	AIFSN	ACK Policy
AC_VO	4	2	2	normal
AC_VI	5	3	5	normal
AC_BE	10	6	5	normal
AC_BK	10	8	12	normal

Table 4 lists the reference EDCA parameter settings and ACK policies for APs in voice and video scenarios.

**Table 4** Reference EDCA parameter settings and ACK policies for APs in voice and video scenarios
Packet Type	ECWmax	ECWmin	AIFSN	ACK Policy
AC_VO	4	2	2	normal
AC_VI	5	3	5	normal
AC_BE	10	6	12	normal
AC_BK	10	8	12	normal

In high-density scenarios, it is recommended that you run the dynamic-edca enable command to enable dynamic EDCA parameter adjustment.
For other scenarios, the default settings are recommended.

Example

# Set EDCA parameters for AC_VO packets of STAs in SSID profile p1.

<HUAWEI> system-view
[HUAWEI] wlan
[HUAWEI-wlan-view] ssid-profile name p1
[HUAWEI-wlan-ssid-prof-p1] wmm edca-client ac-vo aifsn 7 ecw ecwmin 4 ecwmax 10 txoplimit 0