Руководство По Проектированию для Cisco Cisco Aironet 1522 Lightweight Outdoor Mesh Access Point

example, a client at the edge of the cell that might previously have been capable of receiving packets at 
12 Mbps could now receive them at 36 Mbps. Typical measurements of downlink performance with 
ClientLink show as much as 65 percent greater throughput for 802.11a/g clients. By allowing the Wi-Fi 
system to operate at higher data rates and with fewer retries, ClientLink increases the overall capacity 
of the system, which means an efficient use of spectrum resources.

ClientLink in the 1552 access points is based on ClientLink capability available in AP3500s. Therefore, 
the access point has the ability to beamform well to nearby clients and to update beamforming 
information on 802.11ACKs. Therefore, even if there is no dedicated uplink traffic, the ClientLink works 
well, which is beneficial to both TCP and UDP traffic streams. There are no RSSI watermarks, which 
the client has to cross to take advantage of this Beamforming with Cisco 802.11n access points.

ClientLink can beamform to 15 clients at a time. Therefore, the host must select the best 15 if the number 
of legacy clients exceeds 15 per radio. AP1552 has two radios, which means that up to 30 clients can be 
beamformed in time domain.

Although ClientLink is applied to legacy OFDM portions of packets, which refers to 11a/g rates (not 
11b) for both indoor and outdoor 802.11n access points, there is one difference between ClientLink for 
indoor 11n and ClientLink for outdoor 11n. For indoor 11n access points, SW limits the affected rates 
to 24, 36, 48, and 54 Mbps. This is done to avoid clients sticking to a far away AP in an indoor 
environment. SW also does not allow ClientLink to work for those rates for 11n clients because the 
throughput gain is so minimal. However, there is a demonstrable gain for pure legacy clients. For outdoor 
11n access points, we do need more coverage. Thus, three more additional legacy data rates lower than 
24 Mbps have been added. ClientLink for outdoors is applicable to legacy data rates of 6, 9, 12, 18, 24, 
36, 48, and 54 Mbps.

From the 7.2 release onwards, it is not possible to configure ClientLink (beamforming) using the 
controller GUI.

Disable the 802.11a or 802.11b/g network by entering this command:

config {802.11a | 802.11b} disable network

Globally enable or disable beamforming on your 802.11a or 802.11g network by entering this command:

config {802.11a | 802.11b} beamforming global {enable | disable}

The default value is disabled.

After you enable beamforming on the network, it is automatically enabled for all the radios 
applicable to that network type.

Override the global configuration and enable or disable beamforming for a specific access point by 
entering this command:

config {802.11a | 802.11b} beamforming ap Cisco_AP {enable | disable}

The default value is disabled if beamforming is disabled on the network and enabled if beamforming is 
enabled on the network.

Reenable the network by entering this command:

config {802.11a | 802.11b} enable network