Allied Telesis AT-WL2411 - Manual (Page 94)

AT-WL2411 Installation and User’s Guide
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Outbound Frames.
Data frames are forwarded outbound through an IP tunnel if
❑ an end device is known to be attached to an access point on a
remote IP subnet.
❑ the frame type is enabled in the Tunnel Filters menu.
Unicast frames are not flooded. End devices attach to the root access
point, which maintains entries for these devices in its forwarding
database. The database entries indicate the correct subnet for outbound
forwarding.
For TCP/IP applications, IP and ARP frames must be forwarded through
IP tunnels. An IP or ARP frame is only forwarded outbound if the
destination address identifies an end device on the home IP subnet. If
you enable the ARP server in the root access point, you can reduce the
number of ARPs forwarded outbound. For help, see Configuring the
Access Point as an ARP Server on page 58.
Inbound Frames.
Only frame types that are enabled in the Tunnel Filters menu are
forwarded, and the frames are only forwarded inbound if the source IP
address belongs to the home IP subnet. Frames transmitted by servers
or devices that are wired to a remote IP subnet are not forwarded
through IP tunnels if the IP address does not belong to the home subnet.
Only frames from wireless end devices with IP addresses belonging to
the home subnet are forwarded inbound.
Configuring IP
Tunnels
In general, here are some guidelines you can use to configure IP tunnels:
❑ When choosing the home IP subnet, ideally you should choose
the subnet that contains gateways or servers for end devices;
however, these servers may be on other subnet. Note that you can
create a home subnet for end devices. Fixed or variable length
subnet masks can be used; subnet addressing is not required. IP
addresses for end devices must belong to the home subnet.
❑ Identify the root candidates on the home subnet. The root access
point should be an access point that does not otherwise handle a
large volume of traffic.
❑ Configure all access points on the home subnet and remote IP
subnets with the same LAN ID. If IP tunnels are not used to attach
a remote subnet, then access points on that subnet should be
configured with a different LAN ID.