- Preface
- Using the Command-Line Interface
- Using the Web Graphical User Interface
- Configuring WLANs
- Configuring DHCP for WLANs
- Configuring WLAN Security
- Setting Client Count Per WLAN
- Configuring 802.11w
- Configuring Wi-Fi Direct Client Policy
- Configuring 802.11r BSS Fast Transition
- Configuring Assisted Roaming
- Configuring Access Point Groups
- Index
Contents
- Configuring Assisted Roaming
- Finding Feature Information
- Restrictions for Assisted Roaming
- Information About Assisted Roaming
- How to Configure Assisted Roaming
- Configuring Assisted Roaming (CLI)
- Monitoring Assisted Roaming
- Configuration Examples for Assisted Roaming
- Additional References for Assisted Roaming
- Feature History and Information For Performing Assisted Roaming Configuration
Configuring Assisted Roaming
- Finding Feature Information
- Restrictions for Assisted Roaming
- Information About Assisted Roaming
- How to Configure Assisted Roaming
- Monitoring Assisted Roaming
- Configuration Examples for Assisted Roaming
- Additional References for Assisted Roaming
- Feature History and Information For Performing Assisted Roaming Configuration
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the Feature Information Table at the end of this document.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Restrictions for Assisted Roaming
- The assisted roaming feature is supported across multiple switches.
- This feature is supported only on 802.11n capable indoor access points. For a single band configuration, a maximum of 6 neighbors are visible in a neighbor list. For dual band configuration, a maximum of 12 neighbors are visible.
- You can configure assisted roaming only using the switch CLI.
Information About Assisted Roaming
The 802.11k standard allows clients to request neighbor reports containing information about known neighbor access points that are candidates for a service set transition. The use of the 802.11k neighbor list can limit the need for active and passive scanning.
The assisted roaming feature is based on an intelligent and client optimized neighbor list.
Unlike the Cisco Client Extension (CCX) neighbor list, the 802.11k neighbor list is generated dynamically on-demand and is not maintained on the switch. The 802.11k neighbor list is based on the location of the clients without requiring the mobility services engine (MSE). Two clients on the same switch but different APs can have different neighbor lists delivered depending on their individual relationship with the surrounding APs.
By default, the neighbor list contains only neighbors in the same band with which the client is associated. However, a switch exists that allows 802.11k to return neighbors in both bands.
Clients send requests for neighbor lists only after associating with the APs that advertize the RRM (Radio Resource Management) capability information element (IE) in the beacon. The neighbor list includes information about BSSID, channel, and operation details of the neighboring radios.
Assembling and Optimizing the Neighbor List
- The switch searches the RRM neighbor table for a list of neighbors on the same band as the AP with which the client is currently associated with.
- The switch checks the neighbors according to the RSSI (Received Signal Strength Indication) between the APs, the current location of the present AP, the floor information of the neighboring AP from Cisco Prime Infrastructure, and roaming history information on the switch to reduce the list of neighbors to six per band. The list is optimized for APs on the same floor.
Assisted Roaming for Non-802.11k Clients
It is also possible to optimize roaming for non-802.11k clients. You can generate a prediction neighbor list for each client without the client requiring to send an 802.11k neighbor list request. When this is enabled on a WLAN, after each successful client association/reassociation, the same neighbor list optimization is applied on the non-802.11k client to generate the neighbor list and store the list in the mobile station software data structure. Clients at different locations have different lists because the client probes are seen with different RSSI values by different neighbors. Because clients usually probe before any association or reassociation, this list is constructed with the most updated probe data and predicts the next AP that the client is likely to roam to.
We discourage clients from roaming to those less desirable neighbors by denying association if the association request to an AP does not match the entries on the stored prediction neighbor list.
Because both load balancing and assisted roaming are designed to influence the AP that a client associates with, it is not possible to enable both the options at the same time on a WLAN.
How to Configure Assisted Roaming
Configuring Assisted Roaming (CLI)
1.
configure terminal
2.
wireless assisted-roaming floor-bias dBm
3.
wlan wlan-id
4.
assisted-roaming neighbor-list
5.
assisted-roaming dual-list
6.
assisted-roaming prediction
7.
wireless assisted-roaming prediction-minimum count
8.
wireless assisted-roaming denial-maximum count
9.
end
DETAILED STEPS
Monitoring Assisted Roaming
The following command can be used to monitor assisted roaming configured on a WLAN. .
| Command | Description |
|---|---|
| show wlan id wlan-id | Displays the WLAN parameters on the WLAN. |
Configuration Examples for Assisted Roaming
Switch# configure terminal Switch(config)# wireless assisted-roaming floor-bias 10 Switch(config)# end Switch# show wlan id 23
Switch# configure terminal Switch(config)# wlan test1 Switch(config (wlan)# no assisted-roaming neighbor-list Switch(config)(wlan)# end Switch# show wlan id 23
Switch# configure terminal Switch(config)# wlan test1 Switch(config)(wlan)# assisted-roaming prediction Switch(config)(wlan)# end Switch# show wlan id 23
Switch# configure terminal Switch(config)# wireless assisted-roaming prediction-minimum 4 Switch(config)# wireless assisted-roaming denial-maximum 4 Switch(config)(wlan)# end Switch# show wlan id 23
Additional References for Assisted Roaming
Related Documents
| Related Topic | Document Title |
|---|---|
| System management commands | System Management Command Reference (Catalyst 3850 Switches) |
Error Message Decoder
| Description | Link |
|---|---|
|
To help you research and resolve system error messages in this release, use the Error Message Decoder tool. |
https://www.cisco.com/cgi-bin/Support/Errordecoder/index.cgi |
Standards and RFCs
| Standard/RFC | Title |
|---|---|
| 802.11k | — |
MIBs
| MIB | MIBs Link |
|---|---|
| All supported MIBs for this release. |
To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL: |
Technical Assistance
| Description | Link |
|---|---|
|
The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies. To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds. Access to most tools on the Cisco Support website requires a Cisco.com user ID and password. |
Feature History and Information For Performing Assisted Roaming Configuration
| Feature Name | Release | Feature Information |
|---|---|---|
Assisted Roaming |
Cisco IOS XE 3.2SE |
This feature was introduced. |