4.None - the ADSL Router will not send any RIP packets and will ignore any RIP packets received.

The Dynamic Route field controls the format and the broadcasting method of the RIP packets that the ADSL Router 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.

6.4.4 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 ADSL Router supports both IGMP version 1 (IGMP-v1) and IGMP version 2 (IGMP- v2). At start up, the ADSL Router queries all directly connected networks to gather group membership. After that, the ADSL Router periodically updates this information. IP multicasting can be enabled/disabled on the ADSL Router LAN and/or WAN interfaces in the web configurator (LAN; WAN). Select None to disable IP multicasting on these interfaces.

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