Cisco Systems AIRRM3000ACAK9 manual Client Band Steering, 802.11ac Client Recommendations

Understanding 802.11ac and the option module

Figure 71 Current channel allocation plan ETSI Theater.

What’s in the future as far as spectrum allocation?

•In the US there are currently 22/10/5/1 channels with bandwidth 20/40/80/160MHz channels

•With opening up of 5.35-5.47GHz & 5.85-5.925GHz, the number of channels increases to 34/16/8/3

•If the industry manages to take back the TDWR channels, the number of increases to 37/18/9/4 So as time progresses we should see additional channels becoming available.

Client Band Steering

In order to optimize client performance, 802.11ac clients are able to take advantage of ECBF – Explicit Compressed Beam-Forming a IEEE 802.11ac standardized method of Beam-forming (similar in some ways to Cisco’s Client Link) but slightly different as the .11ac client needs to send “sounding information” to the AP and then the AP uses that sounding information (from the client) to best send the signal back to the client using (beam-forming).

Note ECBF only works with 802.11ac clients, Cisco Client Link continues to be used with non-802.11ac clients to improve the overall performance of 802.11n and legacy clients resulting in an improved performance with all clients rather than just 802.11ac clients. This helps maintain solid connections to the AP without having to bounce clients off of the AP using other methods such as signal strength causing needless roaming with the client is not actually engaged in passing traffic.

Note if is it a significant advantage to allow the module to service the 802.11ac clients while the integrated radio services the non-802.11ac clients. Should the 802.11ac client require something the module radio does not support (for example, Cisco Client Extensions “CCX elements” the 802.11ac module will push the client to the integrated radio to service that request.

802.11ac Client Recommendations

At the time of this writing, 802.11ac clients are just now starting to get integrated into smart phones. Devices like Samsung’s Galaxy S4, ZTE’s Grand Memo and the HTC One phone are early to market 802.11ac devices. It is expected that integrated notebooks and tablets (those devices often supporting 2 and 3 spatial streams) will start to emerge later in the calendar year.

Cisco Aironet Series 1600/2600/3600 Access Point Deployment Guide, Release 7.5

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