Originating ip tunnels – Allied Telesis AT-WL2411 User Manual
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AT-WL2411 Installation and User’s Guide
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multicast group by enabling IGMP and by defining a Class D IP multicast
address. The Internet Assigned Numbers Authority has allocated
224.0.1.65 as an inter-access-point protocol (IAPP). You must enter this
address in the IP address list in the root access point. (Note that the
address list may contain other IP addresses.) and in the Multicast
Address field in the other access points.
If you enable IGMP on the root access point, the root access point uses a
Class D IP multicast address to send IP hello packets through IP routers
to access points on other subnets. If you enable IGMP on remote IP
subnets, intermediate IP routers will forward the IP hello packets to
those subnets. Enabling IGMP also has these advantages:
❑ Causes IP hello packets to be forwarded only to those subnets that
participate in the IP multicast group.
❑ Increases redundancy because multiple access points on a remote
subnet can receive IP hello packets.
IP multicast provides an ideal way to distribute IP hello messages.
Normally, you should enable IGMP and configure an IP multicast address
in at least one access point on each remote IP subnet. (Some routers can
provide proxy IGMP services for IP hosts.) IP multicast has the following
advantages:
❑ The user does not have to know unicast or directed broadcast IP
addresses in advance.
❑ IP multicast provides better built-in redundancy than IP unicast,
because any access point can establish an IP tunnel.
IP hello messages are only forwarded to those IP subnets and IP hosts
(such as access points) that participate in the multicast group. Directed
broadcast packets are forwarded to all IP hosts on the target subnet.
Originating IP
Tunnels
The creation of tunnels between the root access point on the home IP
subnet and access points on remote IP subnets is controlled by three
operational parameters:
❑ Enabled/disabled IP ports. A tunnel can never be established on a
disabled IP port.
❑ IP address list
❑ Secondary LAN bridge priority settings