WESM zl Management and Configuration Guide WT.01.03 and greater

1-7
Introduction
ProCurve Wireless Edge Services zl Module
Note Although you configure the Wireless Edge Services zl Module to assign WLAN
traffic to a particular VLAN, a WLAN in the wireless network does not
necessarily have a one-to-one relationship with a VLAN in the Ethernet
network.
The module can tag traffic received from several WLANs for the same VLAN.
Conversely, by implementing user-based VLANs, the module can tag traffic
from different stations in the same WLAN for different VLANs. For more
information about user-based, also called dynamic, VLANs, see “Controlling
Traffic with User-Based Policies” on page 1-35.
After bridging the traffic to the VLAN, the Wireless Edge Services can handle
the traffic in a variety of ways at both Layer 2 and Layer 3. You will learn about
these capabilities later in this chapter; first you must understand more pre-
cisely how the module joins the wireless and wired networks, receiving and
forwarding traffic on its downlink and uplink ports.
The Interface Between the Wireless and Wired
Networks
As the interface between the wireless and wired networks, the Wireless Edge
Services zl Module includes two internal ports:
■ a downlink port
■ an uplink port
The downlink port is associated with the wireless world. It sends traffic to and
receives traffic from the external switch interfaces that connect, either
directly or indirectly, to RPs. The downlink port carries traffic tagged for Radio
Port VLANs.
The uplink port sends traffic to and receives traffic from external switch
interfaces that connect to other devices in the Ethernet network. The uplink
port carries traffic in one or more uplink VLANs—VLANs used in the
Ethernet network.
The following sections describe how the module forwards traffic between RPs
and the Ethernet network, focusing in particular on the VLAN to which the
traffic is assigned at various points in this process.