Switches and Multicast doubt

Hi fellas,

I have a million dollar doubt. Whether switches understand multicast or not.
Its all about the so called I/G bit setting in the MAC frame. If the I bit
is set to 1 then its a multicast address . But unfortunately the broadcast
address also has the I bit set to 1 . So how does a switch differentiate
multicast and broadcast. Is there any method used in cisco switches to
differentiate. Can anyone help me out?

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