Extreme Networks Altitude 4700 Series, Руководство по продукции

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Network Management
Altitude 4700 Series Access Point Product Reference Guide
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6 Click Apply to save any changes to the LAN Configuration screen. Navigating away from the screen
without clicking the Apply button results in all changes to the screen being lost if the prompts are
ignored.
7 Click Undo Changes (if necessary) to undo any changes made. Undo Changes reverts the settings
displayed on the LAN configuration screen to the last saved configuration.
8 Click Logout to securely exit the access point Access Point applet. A prompt displays confirming the
logout before the applet is closed.
Configuring VLAN Support
A Virtual Local Area Network (VLAN) is a means to electronically separate data on the same access point
from a single broadcast domain into separate broadcast domains. The access point can group devices on
one or more WLANs so that they can communicate as if they were attached to the same wire, when in
fact they are located on a different LAN segment. Because VLANs are based on logical instead of
physical connections, they are extremely flexible. By using a VLAN, you can group by logical function
instead of physical location. A maximum of 16 VLANs can be supported on the Access Point. An
administrator can map 16 WLANs to 16 VLANs and enable or disable dynamic VLAN assignment.
VLANs enable organizations to share network resources in various network segments within large areas
(airports, shopping malls, etc.). A VLAN is a group of clients with a common set of requirements
independent of their physical location. VLANs have the same attributes as physical LANs, but they
enable system administrators to group MUs even when they are not members of the same network
segment.
NOTE
A WLAN supporting a mesh network does not need to be assigned to a particular VLAN, as all the traffic
proliferating the mesh network is already trunked. However, if MUs are to be connected to the Mesh WLAN, the
WLAN will need to be tied to a VLAN.
The access point assignment of VLANs can be implemented using Static or Dynamic assignments (often
referred to as memberships) for individual WLANs. Both methods have their advantages and
disadvantages. Static VLAN membership is perhaps the most widely used method because of the
relatively small administration overhead and security it provides. With Static VLANs, you manually
assign individual WLANs to individual VLANs.
Although static VLANs are the most common form of VLAN assignments, dynamic VLAN assignment
is possible per WLAN. Configuring dynamic VLANs entail the access point sending a DHCP request
for device information (such as an IP address). Additional information (such as device MAC address
information) is sent to the access point. The access point sends this MAC address to a host housing a
copy of the Dynamic VLAN database. This database houses the records of MAC addresses and VLAN
assignments. The VLAN database looks up the MAC to determine what VLAN is assigned to it. If it is
not in the database, it simply uses a default VLAN assignment. The VLAN assignment is sent to the
access point. The access point then maps the target WLAN for the assigned VLAN and traffic passes
normally, allowing for the completion of the DHCP request and further traffic.
To create new VLANs or edit the properties of an existing VLAN:
1 Select Network Configuration > LAN from the access point menu tree.
2 Ensure the Enable 802.1q Trunking button is selected from within the LAN Setting field.