WESM zl Management and Configuration Guide WT.01.XX and greater

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Introduction
ProCurve Wireless Edge Services zl Module
The Wireless Edge Services zl Module acts the Wireless LAN System’s brain.
The RPs produce the wireless signal, but the module enforces wireless authen-
tication, generates and encrypts wireless frames, and sets all other policies in
the Wireless LAN System as a whole. A large part of the Wireless Edge Services
zl Module’s duties lie in establishing the settings for WLANs.
A wireless LAN (WLAN), as opposed to a wireless network, refers more
precisely to a set of wireless stations that connect to one or more RPs using
the same SSID, or network name. (For a more technical definition of a WLAN,
as well as its relation to an SSID, an extended service set (ESS), a basic service
set (BSS), and a basic SSID (BSSID), see “ESS” on page 1-58.)
For the purposes of configuring a WLAN on the Wireless Edge Services zl
Module, you can think of a WLAN as a set of parameters on which an RP and
its associated stations agree. These parameters include:
■ the SSID that identifies the WLAN
■ the type of authentication a station must complete before connecting to
the WLAN
■ the encryption algorithms and keys that secure wireless data
■ support for QoS protocols and, in the case of a protocol such as Wi-Fi
Multimedia (WMM), the settings for priority queues
The Wireless Edge Services zl Module defines these settings, and RPs broad-
cast them to wireless stations in beacon and other 802.11 management frames.
For RPs, the module’s WLAN settings also control:
■ whether the RPs broadcast the WLAN’s SSID and respond to probe
requests about the SSID (operate in open system)
■ whether the RPs forward frames directly between wireless stations or
force all traffic to travel through the Wireless Edge Services zl Module
(inter-station blocking)
One of the Wireless Edge Services zl Module’s primary tasks is act as the
interface between the wireless and wired networks. That is, the module
bridges traffic from a WLAN to a VLAN. The WLAN is said to be mapped to
that VLAN.