Allied Telesis AT-WL2411 - Manual (Page 85)

AT-WL2411 Version 1.80 Installation and User’s Guide
85
About
Secondary LANs
and Designated
Bridges
The access point that is responsible for bridging data between the
secondary LAN and the primary LAN is called the designated bridge. In
both types of secondary LANs, the designated bridge acts the same. The
designated bridge must be an access point that has at least one radio set
to Station mode or is the endpoint of an IP tunnel. If more than one
access point meets at least one of these requirements, the access point
with the highest secondary LAN bridge priority is the designated bridge.
If an access point has the highest bridge priority on the secondary LAN,
but it is not in the radio coverage area of an access point on the primary
LAN, it cannot become the designated bridge. In this case, an access
point with a lower bridge priority that is in the radio coverage area or an
access point on the primary LAN becomes the designated bridge. If two
access points have the same secondary LAN bridge priority, the access
point with the highest Ethernet address becomes the designated bridge.
If the designated bridge goes offline, the remaining access points
negotiate to determine which access point becomes the new
designated bridge.
Designated bridges determine if the secondary LAN is bridging or non-
bridging. By enabling the Ethernet bridging parameter on the
designated bridge, all wireless traffic gets dumped raw on the secondary
LAN. You should enable bridging if you have wired hosts on the
secondary LAN that must communicate with a wireless device on the
secondary LAN.
You should enable bridging unless the inbound path through a bridge
or switch does not support roaming. Bridges and switches that adhere to
the IEEE 802.1D standard support roaming. Some proprietary VLAN
switches and ATM LANE bridges do not support roaming. If you disable
the Ethernet bridging parameter on the designated bridge, the wireless
traffic is encapsulated on the secondary LAN, which eliminates
communication from secondary LAN end devices.
If you set the secondary LAN bridge priority to 0 on the designated
bridge, you have a non-bridging secondary LAN; that is, bridging to the
secondary LAN is automatically disabled.