Allied Telesis AT-WA7500 - Manual (Page 116)

5 - Configuring the Spanning Tree
116
About IP Tunnels
The physical boundary of a network is usually defined by the existence
of an IP router. Before IP tunnels technology was developed, wireless
end devices could only operate within the limited coverage area of their
own network and could not roam across IP subnet boundaries. Using IP
tunnel technology, end devices can roam across IP subnet boundaries. IP
tunnel technology safely and transparently coexists with routed IP
installations while supporting mobility for end devices. IP tunnels do the
following:
‰ Enable access points on different remote IP subnets to belong to
the same wireless network.
‰ Support fast roaming of end devices between access points that
are on different IP subnets without losing network connections.
‰ Support end devices using both IP and other routable or
nonroutable protocols.
Only one IP tunnel can exist between the root access point and an access
point (usually the designated bridge) on a remote IP subnet. The root
access point has a one-to-one relationship with each wireless network. All
roaming end devices must have an IP address from the root IP subnet.