Re: What is an IGMPv3 Router's initial current state for amulticast group?

> Note that if one host send the message TO_IN(B) to a router is  
> because there is a change from EXCLUDE filter mode to INCLUDE filter  
> mode.
>
> So when one router receives a TO_IN(B) I have a doubt about if the  
> router should consider the initial state to be INCLUDE({})


The host's initial state is "a filter mode of INCLUDE and an empty  
source list" -- in the above example, there is no accounting of the  
host's preceding state change from this initial state to a filter mode  
of EXCLUDE. If the host's state is a filter mode of EXCLUDE, the  
router should already have created a filter mode of EXCLUDE from the  
TO_EX (B) state-change record sent by the host changing from its  
initial state ("a filter mode of INCLUDE and an empty source list").