Allied Telesis AT-WA7500 - Manual (Page 111)

AT-WA7500 User’s Guide
111
To configure a designated bridge
1. On an access point that is installed on the secondary LAN and within
radio coverage of an access point on the primary LAN, from the Main
Menu select Spanning Tree Settings. The Spanning Tree Settings
screen appears.
2. Configure the LAN ID. All access points that want to participate in the
spanning tree must have the same LAN ID.
3. Set the Root Priority parameter to zero. All access points on the
secondary LAN should have a root priority of zero.
4. Verify that the Enable Ethernet Bridging box is checked.
5. Set the Secondary LAN Bridge Priority to be the highest number of
all access points on the secondary LAN.
6. Set the Secondary LAN Flooding parameter to Enabled.
7. Select Submit Changes to save your changes. To activate your
changes, select Save/Discard Changes from the menu bar then Save
Changes and Reboot. For help, see Saving Configuration Changes
on page 41.
About Data Link
Tunneling
Data link tunneling passes data from wireless end devices
communicating with access points on the same subnet to the root
access point or designated bridge. Use data link tunneling if you have
Ethernet switches that do not support the IEEE 802.1d requirements for
backward learning. Some proprietary VLAN switches and ATM LANE
bridges do not support this standard.
If the access points are connected to different ports on an Ethernet
switch, each time an end device roams to a new access point, it appears
on a different port. Thus, frames sent to the end device from the host will
be sent to the wrong port. If the switch does not support 802.1d, it may
become confused and communications with the end device is
disrupted. Data link tunneling makes end device roaming transparent to
the switch. All the information appears to originate from only one port
on the switch-the port that is connected to the root access point or
designated bridge.
You should also use data link tunneling when you are using IP tunnels to
provide mobility of other routable protocols, such as IPX. In some
network installations, detecting these addresses may generate alarms or
cause switches to behave erroneously. There is no additional forwarding
overhead for disabling bridging in this situation.