This object specifies the name of the subscriber control
policy applied to a target.
The system should assume that the cbpPolicyMapType (defined by
the CISCO-CBP-BASE-CFG-MIB) of the policy is
cbpPmtControlSubscriber (defined by the CISCO-CBP-TYPE-OID-MIB).
This column is valid only if the 'srvSubControl' bit of the
corresponding instance of cdtCommonValid is '1'.