3com 5500-ei pwr Instruccion De Instalación

 

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In this manual, the term “router” refers to a router in the generic sense or a Layer 3 Ethernet switch 

running an IP multicast protocol.  

 

When configuring IGMP, go to these sections for information you are interested in: 

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IGMP Overview 

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As a TCP/IP protocol responsible for IP multicast group member management, the Internet Group 

Management Protocol (IGMP) is used by IP hosts to establish and maintain their multicast group 

memberships to immediately neighboring multicast routers.  

So far, there are three IGMP versions:  

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IGMPv1 (documented in RFC 1112) 

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IGMPv2 (documented in RFC 2236) 

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IGMPv3 (documented in RFC 3376) 

All IGMP versions support the any-source multicast (ASM) model. In addition, IGMPv3 provides strong 

support to the source-specific multicast (SSM) model.  

IGMPv1 manages multicast group memberships mainly based on the query and response mechanism.  

Of multiple multicast routers on the same subnet, all the routers can hear IGMP membership report 

messages (often referred to as reports) from hosts, but only one router is needed for sending IGMP 

query messages (often referred to as queries). So, a querier election mechanism is required to 

determine which router will act as the IGMP querier on the subnet.  

In IGMPv1, the designated router (DR) elected by a multicast routing protocol (such as PIM) serves as 

the IGMP querier.  

For more information about a DR, refer to 

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