This attribute is migrated to the Lp/n Eng Arc Ov attribute of the
same name.
This attribute specifies the number of multicast branches that can be
enabled on the Logical Processor.
A multicast branch is used for cell replication on a Vcc connection
whose Vcc distributionType is pointToMultipoint. A branch
represent one ATM destination for the replicated cells
Increasing the value of this attribute reduces the CQM memory
available for the cell and frame free lists.