5z TO_EX: The filtering mode has changed from Include to Exclude.z ALLOW: The Source Address fields in this Group Record contain a list of the additional sourcesthat the system wishes to hear from, for packets sent to the specified multicast address. If thechange was to an Include source list, these are the addresses that were added to the list; if thechange was to an Exclude source list, these are the addresses that were deleted from the list.z BLOCK: indicates that the Source Address fields in this Group Record contain a list of the sourcesthat the system no longer wishes to hear from, for packets sent to the specified multicast address.If the change was to an Include source list, these are the addresses that were deleted from the list;if the change was to an Exclude source list, these are the addresses that were added to the list.Currently, only the IGMPv1 and IGMPv2 are supported on Switch 5500-EI series Ethernet switches.IGMP ProxyA lot of stub networks (stub domains) are involved in the application of a multicast routing protocol(PIM-DM for example) over a large-scaled network. It is a hard work to configure and manage thesestub networks.To reduce the workload of configuration and management without affecting the multicast connection ofleaf networks, you can configure an IGMP Proxy on a Layer 3 switch in the stub network (Switch Bshown in Figure 3-2). The Layer 3 switch will then forward IGMP join or IGMP leave messages sent bythe connected hosts. After IGMP Proxy is configured, the stub switch is no longer a PIM neighbor but ahost for the exterior network. The Layer 3 switch receives the multicast data of corresponding groupsonly when it has directly attached multicast members.Figure 3-2 Diagram for IGMP proxyFigure 3-2 shows an IGMP Proxy diagram for a stub network. The upstream interface, VLAN-interface 1of Switch B is the proxy interface for the downstream interface VLAN-interface 2.Configure Switch B as follows:
