D-Link xStack DGS-3600 Series User Manual - page 227
xStack DGS-3600 Series Layer 3 Gigabit Ethernet Managed Switch
The states a computer will go through to join or to leave a multicast group are shown below:
Figure 8- 7 . IGMP State Transitions
4
•
For version 2, the host could respond to a group query but in version 3, the host is now capable to answer queries specific to
the group and the source.
IGMP Version 3
The current release of the Switch now implements IGMPv3. Improvements of IGMPv3 over version 2 include:
•
The introduction of the SSM or Source Specific Multicast. In previous versions of IGMP, the host would receive all packets
sent to the multicast group. Now, a host will receive packets only from a specific source or sources. This is done through the
implementation of include and exclude filters used to accept or deny traffic from these specific sources.
•
In IGMP v2, Membership reports could contain only one multicast group whereas in v3, these reports can contain multiple
multicast groups
and multiple sources within the multicast group.
•
Leaving a multicast group could only be accomplished using a specific leave message in v2. In v3, leaving a multicast
group is done through a Membership report, which includes a block message in the group report packet.
IGMP v3 is backwards compatible with other versions of IGMP.
The IGMPv3 Type supported codes are shown below:
Type
Meaning
0x11 Membership
Query
0x12
Version 1 Membership Report
0x16
Version 2 Membership Report
0x17
Version 2 Leave Group
0x22 IGMPv3
Membership
Report
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