D-Link DES-3326 User Manual page 58

Internet Group Management Protocol (IGMP)
End users that want to receive multicast packets must be able to inform nearby routers that they want
to become a multicast group member of the group these packets are being sent to. The Internet Group
Management Protocol (IGMP) is used by multicast routers to maintain multicast group membership.
IGMP is also used to coordinate between multiple multicast routers that may be present on a network
by electing one of the multicast routers as the 'querier'. This router then keep track of the membership
of multicast groups that have active members on the network. IGMP is used to determine whether the
router should forward multicast packets it receives to the subnetworks it is attached to or not. A
multicast router that has received a multicast packet will check to determine if there is at least one
member of a multicast group that has requested to receive multicast packets from this source. If there
is one member, the packet is forwarded. If there are no members, the packet is dropped.
224.0.0.2
224.0.0.3
224.0.0.4
224.0.0.5
224.0.0.6
224.0.0.7
224.0.0.8
224.0.0.9
224.0.0.10
224.0.0.11
224.0.0.12
224.0.0.13
224.0.0.14
224.0.0.15
224.0.0.16
224.0.0.17
224.0.0.18
224.0.0.19
through
224.0.0.225
224.0.0.21
Table 5-10. Reserved Multicast Address Assignment
DES-3326 Layer 3 Fast Ethernet Switch User's Guide
All Routers on this subnet
Unassigned
DVMRP Routers
OSPF IGP Routers
OSPF IGP Designated Routers
ST Routers
ST Hosts
All RIP2 Routers
All IGRP Routers
Mobile Agents
DHCP Servers and Relay Agents
All PIM Routers
RSVP Encapsulation
All CBT Routers
Designated Sbm
All Sbms
VRRP
Unassigned
DVMRP on MOSPF
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