Netcom NB9 - Manual (Page 47)

NB9/NB9W ADSL+ VoIP Router 7
YML790 Rev8
Enable IGMP Snooping IGMP specifies how a host can register a router in order to receive specific multicast traffic.
IGMP Snooping allows the NB9/NB9W to capture IGMP frames. When your NB9/NB9W
hears an IGMP report from a host for a given multicast group it adds the host’s port number
for that group. When the NB9/NB9W hears an IGMP Leave, it removes the host’s port from
the table entry.
Without IGMP snooping, multicast traffic is treated in the same manner as broadcast traffic
- that is, it is forwarded to all ports. With IGMP snooping, multicast traffic of a group is
only forwarded to ports that have members of that group. IGMP Snooping generates no
additional network traffic, allowing you to significantly reduce multicast traffic passing
through your NB9/NB9W.
Save Save the settings.
Save / Reboot Save and reboot with the settings applied.