An entry describes the multicast operational data for the
group/source addresses associated to a port.
The system creates a row in this table for each port and
group/source address configured on the snooping profile
associated to that port.
The system destroy a row on this table when the related
group/source configuration is removed form the profile
associated to that port.
If a port is associated with a profile not defining any static
group/source there will not be any entry for that port on this
table.