Hello M.C.
Actually, in a topology with or without a multicast router, multicast data is not sent to the IGMP Snooping Querier. The purpose of the IGMP Snooping Querier is not to receive and/or process the actual multicast data traffic.
Multicast data is sent from the multicast source to a multicast group address. Hosts interested in receiving this multicast traffic will listen to the multicast group address. The multicast data is sent across the network, targeting this group address, not a specific device like the IGMP Snooping Querier.
The IGMP Snooping Querier’s role is to ask hosts which multicast groups they are interested in. It does this by sending out IGMP queries. These queries are not for data, but rather for membership information. Hosts that want to receive data for a specific multicast group will respond to these queries with IGMP reports, indicating their interest in particular multicast groups.
When a network switch has IGMP Snooping enabled and there is no multicast router present, the switch uses the information gathered by the IGMP Snooping Querier to understand which of its ports have devices interested in specific multicast groups. The switch then intelligently forwards multicast traffic only to those ports that have shown interest in that specific multicast group, rather than flooding the traffic to all ports.
This process helps in optimizing the network by ensuring that multicast traffic is only sent to network segments where there are interested recipients, reducing unnecessary network load and improving overall network performance. Does that make sense?
I hope this has been helpful!
Laz