ZyXEL Communications MAX-306M1, User Manual

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Chapter 7 The LAN Configuration Screens
User’s Guide
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• None - the WiMAX Modem will not send any RIP packets and will ignore any RIP
packets received.
The Version field controls the format and the broadcasting method of the RIP
packets that the WiMAX Modem sends (it recognizes both formats when
receiving).
RIP-1
is universally supported; but RIP-2 carries more information.
RIP-1 is probably adequate for most networks, unless you have an unusual
network topology.
Both
RIP-2B
and
RIP-2M
sends the routing data in RIP-2 format; the difference
being that
RIP-2B
uses subnet broadcasting while
RIP-2M
uses multicasting.
7.6.6 Multicast
Traditionally, IP packets are transmitted in one of either two ways - Unicast (1
sender - 1 recipient) or Broadcast (1 sender - everybody on the network).
Multicast delivers IP packets to a group of hosts on the network - not everybody
and not just 1.
IGMP (Internet Group Multicast Protocol) is a network-layer protocol used to
establish membership in a Multicast group - it is not used to carry user data. IGMP
version 2 (RFC 2236) is an improvement over version 1 (RFC 1112) but IGMP
version 1 is still in wide use. If you would like to read more detailed information
about interoperability between IGMP version 2 and version 1, please see sections
4 and 5 of RFC 2236. The class D IP address is used to identify host groups and
can be in the range 224.0.0.0 to 239.255.255.255. The address 224.0.0.0 is not
assigned to any group and is used by IP multicast computers. The address
224.0.0.1 is used for query messages and is assigned to the permanent group of
all IP hosts (including gateways). All hosts must join the 224.0.0.1 group in order
to participate in IGMP. The address 224.0.0.2 is assigned to the multicast routers
group.
The WiMAX Modem supports both IGMP version 1 (IGMP-v1) and IGMP version 2
(IGMP-v2). At start up, the WiMAX Modem queries all directly connected
networks to gather group membership. After that, the WiMAX Modem periodically
updates this information. IP multicasting can be enabled/disabled on the WiMAX
Modem LAN and/or WAN interfaces in the web configurator (LAN; WAN). Select
None to disable IP multicasting on these interfaces.