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In a switched Ethernet network is there a use-case for having VLAN tags for frames that have a multicast MAC as destination address?

I cannot find a use-case because:

VLANs are generally used for limiting the broadcast domain and for security, both of which can be achieved using multicast frames when there is a switch in the network which knows which multicast MAC address is reachable on which all ports.

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  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could provide and accept your own answer.
    – Ron Maupin
    Aug 15 '17 at 5:00
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Yes, they are relevant. Multicast frames are layer 2 constructs, so they are still bound by the layer 2 domain. You still need a router to forward multicast frames to another L2 domain.

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Multicast is a form of broadcast at layer-2, and it is limited, just like broadcast, to a layer-2 domain (VLAN).

VLAN tags are used on trunk interfaces so that the traffic for each VLAN can be distinguished from traffic for other VLANs.

Multicast traffic on one VLAN will be confined to that VLAN, and any multicast traffic on a trunk will be tagged for the VLAN (except if it is on a native VLAN).

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