Notes on operating AutoWDS

Owing to technical restrictions, the applications of AutoWDS are limited to certain specific application scenarios. Please carefully observe the general remarks in this chapter to avoid possible complications. The items listed here are intended to supplement the remarks elsewhere in the AutoWDS chapter, so some redundancies are possible.

Important: If you are operating DFS in combination with AutoWDS, you should set the continuation time for autonomous operation of the AutoWDS profile to at least 2 minutes. After the downtime of a P2P connection, this extra minute allows for the one-minute DFS scan, after which the CAPWAP layer restores the CAPWAP connection to the WLC via the P2P connection.
Important: If possible, ensure that all APs on each physical WLAN interface (WLAN-1, WLAN-2) consistently use the same frequency band (2.4 GHz or 5 GHz) to exclude any potential problems with the automatic topology configuration.

The following is a overview of the suitability of AutoWDS for certain application scenarios.

Suitable:

Use of a dedicated physical WLAN interface for the P2P links.





Partly suitable:

Use of single physical WLAN interface simultaneously for the AutoWDS uplink and downlink (repeater mode) where all P2P links operate on the same radio channel.





Difficulties can arise from the hidden station problem or throughput loss due to multiple transmissions.

Unsuitable:

Use of a physical WLAN interface simultaneously for AutoWDS uplink and downlink (repeater mode) during outdoor operations with more than one hop in the 5-GHz band.





In repeater mode, the physical WLAN interface has a dual role: In the direction of the WLC the interface operates as a master, while in the direction of neighboring APs it operates as a slave. For this purpose, all APs necessarily operate on the same radio channel. However, if the DFS feature detects signals, the APs are required to stop transmitting on the affected frequencies. This means that the APs cannot inform the WLC about the DFS event and the WLC cannot initiate a change of frequency for the network. As a result, the affected APs are potentially permanently separated from the network.

Figure 3. Connection lock after DFS detection



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