Technical data

Adding an ESS with the CLI

the CLI using the ESSID command apsdsupport or you can configure APSD support for

an ESSID from the Web UI (Configuration > Wireless > ESSID and then turn on

U-APSD).

Configure U-APSD

APSD settings are configured per ESS and APSD support is on by default; this setting

only affects AP300/AP400/AP1000. To configure APSD from the Web UI, click Config-

uration > Wireless > ESS > select an ESS from the list > set APSD Support to on.

To turn on/off APSD support with the CLI, use the command apsd-support for the

ESSID as shown in this example:

default# configure terminal

default(config)# essid apsd

default(config-essid)# no apsd-support

default(config-essid)# end

Virtual Cell Overflow Feature

If you are using AP300/AP400 models, you can now temporarily expand the capacity

of a Virtual Cell for peak usage times or areas. This feature, called Vcell Overflow,

works by pairing a Virtual Cell ESS with a non-Virtual Cell ESS. The overflow ESS auto-

matically inherits the parameters of the Virtual Cell ESS (except the setting for

Virtual Cell). The non-Virtual Cell ESS is not used unless the Virtual Cell ESS is

maxed-out; when this happens, the Virtual Cell ESS overflows into the other ESS as

needed. The two ESS Profiles share an SSID so that clients seamlessly move back and

forth. The overflow decision is based on the percentage of airtime spent on beacons

crossing a threshold; when the percentage reaches 50%, clients start to overflow.

When Would I Use Virtual Cell Overflow?

This feature is designed for a high density deployment and provides a solution for

bottlenecks caused by transmitting beacons. Virtual Cell Overflow is useful in these

situations:

 Beacon overhead has become very high due to the legacy b devices.

 A very dense network is consuming a lot of airtime with beacons.

 For whatever reason, you Virtual Cell and non-Virtual Cell must co-exist on

AP300/AP400. For example, some phones’ best practices recommend non-Virtual

Cell, and it’s OK to have low bandwidth on these phones.

Be aware that Virtual Cell Overflow has these tradeoffs:

 Trade-off between mobility and performance

 Trade-off between density and performance

 Not a solution to get good performance for overflow clients