Authentication, Authorization, Accounting Overrides
The Allow Authentication, Authorization, Accouting (AAA) Override option of a WLAN enables you to configure the WLAN for authentication. It enables you to apply VLAN tagging, QoS, and ACLs to individual clients based on the returned RADIUS attributes from the AAA server.
AAA overrides for FlexConnect access points introduce a dynamic VLAN assignment for locally switched clients. AAA overrides for FlexConnect also support fast roaming (Opportunistic Key Caching [OKC]/ Cisco Centralized Key management [CCKM]) of overridden clients.
VLAN overrides for FlexConnect are applicable for both centrally and locally authenticated clients. VLANs can be configured on FlexConnect groups.
If a VLAN on the AP is configured using the WLAN-VLAN, the AP configuration of the corresponding ACL is applied. If the VLAN is configured using the FlexConnect group, the corresponding ACL configured on the FlexConnect group is applied. If the same VLAN is configured on the FlexConnect group and also on the AP, the AP configuration, with its ACL takes precedence. If there is no slot for a new VLAN from the WLAN-VLAN mapping, the latest configured FlexConnect group VLAN is replaced.
If the VLAN that was returned from the AAA is not present on the AP, the client falls back to the default VLAN configured for the WLAN.
Before configuring a AAA override, the VLAN must be created on the access points. These VLANs can be created by using the existing WLAN-VLAN mappings on the access points, or by using the FlexConnect group VLAN-ACL mappings.
AAA Override for IPv6 ACLs
In order to support centralized access control through a centralized AAA server such as the Cisco Identity Services Engine (ISE) or ACS, the IPv6 ACL can be provisioned on a per-client basis using AAA Override attributes. In order to use this feature, the IPv6 ACL must be configured on the controller and the WLAN must be configured with the AAA Override feature enabled. The AAA attribute for an IPv6 ACL is Airespace-IPv6-ACL-Name similar to the Airespace-ACL-Name attribute used for provisioning an IPv4-based ACL. The AAA attribute-returned contents should be a string that is equal to the name of the IPv6 ACL as configured on the controller.
AAA Overrides of Bidirectional Rate Limiting on an AP and Controller
You can have AAA overrides for FlexConnect APs to dynamically assign QoS levels and/or bandwidth contracts for both locally switched traffic on web-authenticated WLANs and 802.1X-authenticated WLANs. Both upstream and downstream parameters are sent to the corresponding AP.
Upstream/Downstream | Local Mode | FlexConnect Central Switching | FlexConnect Local Switching | FlexConnect Standalone |
---|---|---|---|---|
Per-Client Downstream | AP | AP | AP | AP |
Per-Client Upstream | AP | AP | AP | AP |
Per-SSID Downstream | AP | AP | AP | AP |
Per-SSID Upstream | AP | AP | AP | AP |
There is an option to select the downstream rate limit through the QoS profile page. Users that already make use of QoS profiles functionality have additional granularity and capabilities.
The trade-off with configuring the rate limits under the QoS profile is that there are only four QoS profiles available. Thus, there are only four sets of configuration options to use.
Also, because the QoS profile is applied to all clients on the associated SSID, all clients connected to the same SSID will have the same rate limited parameters.
AAA | QoS Profile of AAA | WLAN | QoS Profile of WLAN | Applied to Client |
---|---|---|---|---|
100 Kbps | 200 Kbps | 300 Kbps | 400 Kbps | 100 Kbps |
X | — | — | — | 200 Kbps |
X | X | — | — | 300 Kbps |
X | X | X | — | 400 Kbps |
X | X | X | X | Unlimited |
Important Guidelines
-
Rate limiting is supported for APs in Local and FlexConnect mode (both Central and Local switching).
-
When the controller is connected and central switching is used, the controller handles the downstream enforcement of per-client rate limit only.
-
APs handle the enforcement of the upstream traffic and per-SSID rate limit for downstream traffic.
-
For the locally switched environment, both upstream and downstream rate limits will be enforced on the AP. The enforcement on the AP will take place in the dot11 driver. This is where the current classification exists.
-
In both directions, per-client rate limit is applied/checked first and per-SSID rate limit is applied/checked second.
-
The WLAN rate limiting will always supercede the global QoS setting for WLAN and user.
-
Rate limiting works only for TCP and UDP traffic. Other types of traffic (IPSec, GRE, ICMP, CAPWAP, etc) cannot be limited.
-
Using AVC rule, you can limit the bandwidth of a particular application for all the clients joined on the WLAN. These bandwidth contracts coexist with per-client downstream rate limiting. The per-client downstream rate limits takes precedence over the per-application rate limits.
-
Bidirectional rate limiting (BDRL) configuration in a mobility Anchor-Foreign setup needs to be done both on Anchor and Foreign controller. As a best practice, we recommend that you do identical configuration on both the controllers to avoid breakage of any feature.
-
Per WLAN BDRL is supported on these currently supported Cisco Wave1 APs: 1600, 2600, 3600, 1700, 2700, 3700, and 3500.
-
For information about BDRL support on Cisco Wave 2 APs, see the FlexConnect Feature Matrix section in the Feature Matrix for Cisco Wave 2 Access Points and Wi-Fi 6 (802.11ax) Access Points.
-
BDRL is not supported in mesh platforms. On Cisco Virtual Wireless Controller (vWLC), per-client downstream rate limiting is not supported in FlexConnect central switching.
-
In Release 8.5, in anchor-foreign scenario with Cisco Wave 2 APs, only per-client downstream works. The per-client upstream, per-SSID downstream, and per-SSID upstream are not supported. However, all of these are supported in Cisco Wave 1 APs.
In Release 8.8, in anchor-foreign scenario with Cisco Wave 2 APs, all both per-client upstream and downstream and per-SSID upstream and downstream are supported, provided that the configuration is the same in both and anchor and foreign controllers.
Related Documentation: Wireless Bi-Directional Rate Limiting Deployment Guide
This section contains the following subsections: