3com S7906E Instruccion De Instalación

 

1-12 

This configuration takes effect for dynamically joined multicast groups but not the statically configured 

multicast groups. 

 

 

For the configuration tasks described in this section:  

z 

Configurations performed in IGMP view are effective on all interfaces, while configurations 

performed in interface view are effective on the current interface only. 

z 

If the same feature is configured in both IGMP view and interface view, the configuration performed 

in interface view is given priority, regardless of the configuration sequence.  

 

Before adjusting IGMP performance, complete the following tasks: 

z 

Configure any unicast routing protocol so that all devices in the domain are interoperable at the 

network layer.  

z 

Configure basic functions of IGMP  

Before adjusting IGMP performance, prepare the following data: 

z 

Startup query interval 

z 

Startup query count 

z 

IGMP general query interval  

z 

IGMP querier’s robustness variable  

z 

Maximum response time for IGMP general queries 

z 

IGMP last-member query interval  

z 

Other querier present interval 

IGMP queries include group-specific queries and group-and-source-specific queries, and multicast 

groups change dynamically, so a device cannot maintain the information for all multicast sources and 

groups, For this reason, when receiving a multicast packet but unable to locate the outgoing interface 

for the destination multicast group, an IGMP router needs to leverage the Router-Alert option to pass 

the multicast packet to the upper-layer protocol for processing. For details about the Router-Alert option, 

refer to RFC 2113.  

An IGMP message is processed differently depending on whether it carries the Router-Alert option in 

the IP header: