Technical data

Chapter 5

Configuring an ESS

A basic service set (BSS) is the basic building block of an IEEE 802.11 wireless LAN;

one access point together with all associated clients is called a BSS. An AP acquires

its clients by broadcasting its name (SSID) which is picked up by clients within range.

Clients can then respond, establishing a connection. It is legitimate for multiple

access points to share the same SSID if they provide access to the same network as

part of an Extended Service Set (ESS). You can establish different kinds of ESS for

different situations such as:

 a VLAN that supports multiple access points per ESS.

 several different ESSs on one physical access point.

 a VLAN for each ESS to separate network traffic. You can also specify that a VLAN

be shared between multiple ESSs.

 an ESS that supports just one person.

 an ESS for a remote AP, such as in a branch office. That AP can additionally

support ESSs for local traffic.

 an ESS divided to support different security requirements. For example, you can

set up an ESS such that clients who use WPA are placed into a VLAN named vlan10,

and clients who enter the network in Open mode are placed into a VLAN named

vlan20. (For information about configuring security, see Chapter 8, “Configuring

Security” on page 113).

The Meru Wireless LAN System also allows you to customize a beacon per ESS to

support different access point settings, such as base or supported transmit rates,

different BSSs, different beacon intervals, and different DTIM periods. This beacon

customization allows service customization for each ESS, as well as more flexibility

in supporting different clients and services.

ESS profiles for a controller can also be configured from E(z)RF Network Manager. You

can tell where an ESS was configured by checking the read-only field Owner. The

Owner is either nms-server or controller. AP1000 can simultaneously support an ESS

with Virtual cell and another ESS without Virtual Cell; AP300 cannot do this.