An indication of whether NCDP is presently running on an
ATM Network-to-Network interface. When NCDP is enabled for
an interface, the interface is an active member of the clock
distribution topology.
After this object is instantiated by the agent the
managed system initializes the value of this object to 'true'.
By default, all Network-to-Network interfaces participate in
NCDP until it's disabled by setting the value of this object
to 'false'.