Wireless/Redundant Edge Services xl Module Management and Configuration Guide WS.02.xx and greater

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Wireless Local Area Networks (WLANs)
Configuring a WLAN
Setting Basic Configuration Options: SSID and Interface
You must set the following options in the Configuration section of a WLAN’s
Edit screen:
■ the SSID
The SSID identifies the WLAN; stations associated to the same SSID are
in the same WLAN regardless of the RP radio to which they have associ-
ated. The SSID is sometimes called the network name; it is the name that
users see when they search for wireless networks to which to connect (as
long as the WLAN operates in open system).
Because SSIDs distinguish WLANs from each other, each WLAN must
have a unique SSID.
■ the interface associated with the WLAN
It is the Wireless Edge Services xl Module’s role to ready traffic received
from RPs for transmission into the Ethernet network. The module
removes the 802.11 header and adds an Ethernet header. This header
includes a 802.1Q tag for a particular VLAN. In other words, the module
assigns stations in the WLAN to a VLAN.
By default, the module places all wireless traffic in VLAN 1. If your
network only uses one subnetwork, this configuration is adequate. Many
networks, however, include multiple subnetworks, of which VLAN 1 is
sometimes the management VLAN. Because of security, as well as other,
concerns, you should often assign the WLAN a new VLAN ID.
You can tag wireless traffic for one of your network’s user VLANs, or you
can create a separate VLAN entirely dedicated to wireless stations. If you
choose the second option, of course, you must ensure traffic can reach
its destination. For example, configure the Wireless Edge Services xl
Module to route traffic. You might also need to configure Dynamic Host
Configuration Protocol (DHCP) and Network Address Translation (NAT)
services on the VLAN. See “Reserving VLANs for Wireless Users” on
page 1-18 of Chapter 1: Introduction for more explanation.
Instead of mapping the WLAN to a VLAN, you can map it to a tunnel
interface. See Chapter 12: Configuring Tunnels with Generic Routing
Encapsulation for more information on this topic.
Finally, your network might include a RADIUS server that assigns users
to VLANs based on their identities. Enable dynamic VLANs to allow the
module to enforce these assignments. (The VLAN ID that you configure
manually remains the default for users not assigned to a dynamic VLAN.)
You can also enter a description, but this setting is optional.