P-661HNU Series Support Notes
61
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9. Using IP Multicast
What is IP Multicast ?
Traditionally, IP packets are transmitted in two ways - unicast or broadcast.
Multicast is a third way to deliver IP packets to a group of hosts. Host groups
are identified by class D IP addresses, i.e., those with "1110" as their
higher-order bits. In dotted decimal notation, host group addresses range from
224.0.0.0 to 239.255.255.255. Among them, 224.0.0.1 is assigned to the
permanent IP hosts group, and 224.0.0.2 is assigned to the multicast routers
group.
IGMP (Internet Group Management Protocol) is the protocol used to support
multicast groups. The latest version is version 2 (see RFC2236). IP hosts use
IGMP to report their multicast group membership to any immediate-neighbor
multicast routers so the multicast routers can decide if a multicast packet
needs to be forwarded. At start up, the P-661HNU-Fx queries all directly
connected networks to gather group membership.
After that, the P-661HNU-Fx updates the information by periodic queries. The
P-661HNU-Fx implementation of IGMP is also compatible with version 1. The
multicast setting can be turned on or off on Ethernet and remote nodes.
P-661HNU-Fx supports IGMP v1 ,v2 and IGMP v3 without source filtering.
IP Multicast Setup
Enable IGMP in P-661HNU-Fx's remote node in Web Configurator, Advanced
Setup,
Network Setting-> Broadband
