2.
The querier sends a Group-Specific Query to determine whether there are any remaining hosts in
the group. There must be at least one receiver in a group on a subnet for a router to forward
multicast traffic for that group to the subnet.
3.
Any remaining hosts respond to the query according to the delay timer mechanism (refer to
Adjusting Query and Response Timers
). If no hosts respond (because there are none remaining in
the group), the querier waits a specified period and sends another query. If it still receives no
response, the querier removes the group from the list associated with forwarding port and stops
forwarding traffic for that group to the subnet.
IGMP Version 3
Conceptually, IGMP version 3 behaves the same as version 2. However, there are differences.
• Version 3 adds the ability to filter by multicast source, which helps multicast routing protocols avoid
forwarding traffic to subnets where there are no interested receivers.
• To enable filtering, routers must keep track of more state information, that is, the list of sources that
must be filtered. An additional query type, the Group-and-Source-Specific Query, keeps track of state
changes, while the Group-Specific and General queries still refresh the existing state.
• Reporting is more efficient and robust: hosts do not suppress query responses (non-suppression
helps track state and enables the immediate-leave and IGMP snooping features), state-change reports
are retransmitted to insure delivery, and a single membership report bundles multiple statements from
a single host, rather than sending an individual packet for each statement.
The version 3 packet structure is different from version 2 to accommodate these protocol
enhancements. Queries are still sent to the all-systems address 224.0.0.1, as shown in the following
illustration, but reports are sent to the all IGMP version 3-capable multicast routers address 244.0.0.22, as
shown in the second illustration.
Figure 43. IGMP Version 3 Packet Structure
410
Internet Group Management Protocol (IGMP)
Содержание S4820T
Страница 1: ...Dell Configuration Guide for the S4820T System 9 8 0 0 ...
Страница 282: ...Dell 282 Control Plane Policing CoPP ...
Страница 569: ...Figure 62 Inspecting Configuration of LAG 10 on ALPHA Link Aggregation Control Protocol LACP 569 ...
Страница 572: ...Figure 64 Inspecting a LAG Port on BRAVO Using the show interface Command 572 Link Aggregation Control Protocol LACP ...
Страница 573: ...Figure 65 Inspecting LAG 10 Using the show interfaces port channel Command Link Aggregation Control Protocol LACP 573 ...
Страница 617: ...mac address table static multicast mac address vlan vlan id output range interface Microsoft Network Load Balancing 617 ...
Страница 622: ...Figure 81 Configuring Interfaces for MSDP 622 Multicast Source Discovery Protocol MSDP ...
Страница 623: ...Figure 82 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 623 ...
Страница 624: ...Figure 83 Configuring PIM in Multiple Routing Domains 624 Multicast Source Discovery Protocol MSDP ...
Страница 629: ...Figure 86 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 629 ...
Страница 630: ...Figure 87 MSDP Default Peer Scenario 3 630 Multicast Source Discovery Protocol MSDP ...
Страница 751: ...10 11 5 2 00 00 05 00 02 04 Member Ports Te 1 2 1 PIM Source Specific Mode PIM SSM 751 ...
Страница 905: ...Figure 112 Single and Double Tag First byte TPID Match Service Provider Bridging 905 ...
Страница 979: ...6 Member not present 7 Member not present Stacking 979 ...
Страница 981: ...storm control Storm Control 981 ...
Страница 999: ... Te 1 1 0 INCON Root Rootguard Te 1 2 0 LIS Loopguard Te 1 3 0 EDS Shut Bpduguard Spanning Tree Protocol STP 999 ...
Страница 1103: ...Figure 134 Setup OSPF and Static Routes Virtual Routing and Forwarding VRF 1103 ...