Allied Telesis AT-WA7501, AT-WA7500 manual AP4

AT-WA7500 and AT-WA7501 Installation and User’s Guide

Host

RootAP2

Primary LAN

(root IP subnet)

IP router

IP network
IP router	Designated	AP4	AP5
	bridge

Secondary LAN (remote IP subnet)

IP tunnels use encapsulation to establish a virtual LAN (VLAN) segment through IP routers. The VLAN segment includes the root IP subnet and logically extends to include end devices attached to access points on remote IP subnets. IP tunnels are branches in the spanning tree topology.

Any access point on a secondary LAN that can receive IP hello messages can be the endpoint of an IP tunnel. Usually, the access point that is the endpoint of an IP tunnel is also the designated bridge. After an IP tunnel is formed between the root access point and an access point on a remote IP subnet, end devices can roam to the remote IP subnet. End devices must have an IP address from the root IP subnet. However, there are no address restrictions for non-IP end devices. When end devices roam to the remote IP subnet, their data is IP tunneled back to the root IP subnet (where it belongs) and everything works properly.

If you have a DHCP server in your network, it must be on the root IP subnet. All access points on secondary LANs must have permanent IP addresses. On the root access point, you must allow IP multicast frames to pass.

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