DES-3326 Layer 3 Fast Ethernet Switch User’s Guide

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

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

Table 5-10. Reserved Multicast Address Assignment

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.

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D-Link DES-3326 manual Internet Group Management Protocol Igmp