Wireless Quality of Service
A wireless Quality of Service policy is a network management policy that
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prioritizes specific types of wireless traffic by giving preferential treatment
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applies different rules to SSID and client targets in both upstream and downstream directions, and
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supports traffic marking, rate limiting (policing), mobility features, and compatibility with advanced controller functions.
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Upstream traffic: The flow of data from a wireless source to a wired target.
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Downstream traffic: The flow of data from a wired source to a wireless target.
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Target: The entity (SSID or client) where the QoS policy is enforced.
Additional reference information
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Without QoS, network devices transmit packets with best-effort service, offering no guarantees for reliability, delay bounds, or throughput. Wireless QoS policies enhance the network by ensuring that traffic with higher priority receives preferential treatment. This policy improves overall performance for critical applications.
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Applying a wireless QoS policy to prioritize voice traffic on an SSID ensures that calls suffer less latency or jitter compared to general web browsing traffic.
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Rate limiting is used to prevent a single client from consuming excessive bandwidth and to maintain fair usage for all wireless clients.
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A network with no configured QoS policies treats all wireless traffic equally, which can lead to poor performance for delay-sensitive applications.
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QoS policies designed for wired networks do not automatically apply to wireless environments, as wireless traffic has unique constraints.
Wireless QoS targets
This section describes the various wireless QoS targets available on a device.
Service set identifiers policies
An Service Set Identifiers (SSID) policy is a wireless network configuration policy that
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controls the application of QoS settings to a wireless SSID in both ingress and egress directions
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applies per AP and per SSID, and
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allows configuration of policing and marking actions on SSID traffic.
If an SSID policy is not configured, no QoS policy is applied to the SSID.
Client policies
Client policies are applicable in the ingress and egress direction. You can configure policing and marking policies on clients. AAA override is also supported.
Supported QoS features on wireless targets
Wireless controllers support various QoS features to manage traffic and ensure optimal performance for both SSIDs and client devices. These tables show the supported features, applicable directions, and configuration modes for wireless targets.
This table describes the various features available on wireless targets.
| Target | Features | Direction where policies Are applicable |
|---|---|---|
| SSID |
|
Upstream and downstream |
| Client |
|
Upstream and downstream |
This table describes the various features available on wireless targets.
|
Policy action types |
Wireless target support | |
|---|---|---|
|
Local mode |
FlexConnect Mode |
|
|
Police |
Supported |
Supported |
|
Set |
Supported |
Supported |
This table describes the various features available on wireless targets.
|
Set action types |
Supported | |
|---|---|---|
|
Local mode |
FlexConnect mode |
|
|
set dscp |
Supported |
Supported |
|
set qos-group |
Supported |
Not Supported |
|
set wlan user-priority (downstream only) |
Supported (BSSID only) |
Supported (BSSID only) |
Wireless QoS mobility
A wireless QoS mobility feature is a network mobility mechanism that
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enables configuration of QoS policies to provide consistent service for wireless clients
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supports seamless roaming between different access points and network devices and
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maintains the same service levels no matter where the client connects in the network.
Wireless client roaming can occur in two forms:
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Intra-device roaming: Roaming across access points managed by the same device.
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Inter-device roaming: Roaming across access points managed by different devices.
Additional reference information
![]() Note |
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Precious metal policies for wireless QoS
Precious metal policies for wireless QoS are system-defined QoS policies
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assign different service levels to wireless network traffic based on pre-set categories,
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remain unmodifiable, cannot be removed by administrators, and
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affect packet attributes, such as 802.11e (WMM) and DSCP fields, when policies are applied.
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Platinum: Used for VoIP clients, assigns the highest priority.
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Gold: Used for video clients, assigns high priority, lower than platinum.
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Silver: Used for best-effort traffic, assigns standard priority.
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Bronze: Used for Non-Real-Time (NRT) traffic, assigns the lowest priority.
Additional reference information
Preconfigured precious metal policies are available on wireless controllers. Administrators cannot modify or delete these policies. AAA mechanisms may push client metal policies. These policies determine packet scheduling and marking on the network.
In FlexConnect local switching mode, APs do not enforce QoS metal policy ceiling limits for upstream traffic. Limit enforcement occurs at the controller exit point. The AP does not change DSCP values.
See the Metal policy format section for more information about metal policy formats.
See the Metal policy map section for more information about metal policies.
Precious metal policies for wireless QoS
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Assigning the platinum policy to VoIP devices ensures minimal latency for voice communication.
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Assigning the gold policy to video streaming clients optimizes traffic for media applications.
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The silver policy applied to laptops browsing the internet handles general best-effort data.
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The bronze policy used for devices performing background updates minimizes their network priority.
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Custom user-defined QoS policies that administrators can modify or remove are not considered precious metal policies.
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Policies that do not map traffic types to platinum, gold, silver, or bronze levels are not included.
Prerequisites for wireless QoS
Before you configure wireless QoS, make sure you understand key concepts and network factors to ensure effective deployment.
The required prerequisites include:
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Understand wireless concepts and network topologies.
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Understand QoS implementation.
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Modular QoS CLI (MQC). To learn more about Modular QoS CLI, see the MQC guide.
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Understand the types of applications used and the traffic patterns on your network.
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Understand your network’s bandwidth requirements and speed.
Restrictions for QoS on wireless targets
QoS policy application on wireless targets (such as SSIDs, BSSIDs, and wireless clients) has these key restrictions and considerations.
General Restrictions
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QoS policy application on wireless targets (such as Service Set Identifier (SSID), BSSID, and wireless clients) includes these key restrictions and considerations:
Hierarchical (parent policy and child policy) QoS is not supported.
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Configure SSID and client targets only with marking and policing policies.
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You can assign only one policy per target for each direction.
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Although class maps in a policy map can have different types of filters, only one marking action (set dscp) is supported.
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Only one set action per class is supported.
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You cannot use access group matching.
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Access points in flex mode do not support Access Control List (ACL) matching for local switching traffic.
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SIP Call Admission Control (CAC) is not supported on central switching mode.
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From Cisco IOS XE Amsterdam 17.3.1 and later, SIP Call Admission Control (CAC) is not supported.
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Do not apply QoS on the WMI interface because it may reboot the controller.
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AP QoS statistics for each radio stop updating after 32,768 minutes (546 hours). At that point, the offered rate shows zero and the minute counter stops increasing.
The system calculates rates within a 32,768-minute window (546 hours). After 32,768 minutes, the data rate calculation is zero.
To reset the statistics, run this command to clear the QoS statistics for the target policy map and SSID: show policy-map interface wireless ssid profile-name <wlan_profile_name> radio type <radio_type> ap name <AP_name> input clear
AP Side Restrictions
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In Cisco Embedded Wireless Controller, FlexConnect local switching, and Software-Defined Access (SDA) deployments, the AP enforces QoS policies and rate-limiting actions at the per-flow (5-tuple) level, not per client.
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For FlexConnect local switching with local authentication and AAA override enabled (using an external AAA server), you can use only air space VLAN and ACL as AAA overrides. QoS and other overrides are not available.
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Rate limiting per SSID is not supported in FlexConnect local switching mode. For rate limiting to work as expected, FlexConnect central switching mode should be used.
Control Plane Rate Limiting and Policing
You do not need to configure control plane rate limiting or policing. Built-in mechanisms, such as policers, protect the CPU from control plane traffic. Migrations from AireOS to IOS-XE handle this automatically.
Restriction: Client connectivity and TCP packet drops on SSIDs with AAA rate limiting
Do not configure rate limits or AAA overrides on Cisco ISE for any SSID where AAA rate limiting is applied. These settings can cause the APs in local mode to drop TCP packets. In such a scenario, use Modular QoS CLI (MCQ)-based method only for configuring Quality of Service (QoS) and rate limiting.
Behavior explanation
When a client connects to an SSID with AAA rate limiting configured on APs in local mode, the AP forwards ICMP, DHCP, and DNS packets to the controller but drops TCP packets. This issue is caused when rate limits are configured on Cisco ISE and AAA overrides are in place. You can verify that TCP packets are dropped using the show datapath drop trace comand.
Workaround
Review the configuration of rate limits and consider removing them or adjusting the settings to avoid dropping TCP packets. Use Modular QoS CLI (MCQ)-based method only for configuring Quality of Service (QoS) and rate limiting. For more information about the MCQ-based method, see Configure QoS Rate Limit on Catalyst 9800 Wireless Controllers.
Verify client connectivity
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To observe the AP configuration, use this command. show ap dot11 5ghz network -
To verify the AP configuration, use this command. show ap dot11 5ghz network -
To check the client summary, use this command. show wireless client summary -
To verify client details and troubleshoot connectivity issues, use this command: show wireless client mac-address MAC-address detail

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