dtmTimeSourceCalibrationReference
The index of the dtmTimeSourceEntry of the time source that is used as calibration reference. The special value 0 is used if the field is not set, and means that the node clock is used as reference.
The index of the dtmTimeSourceEntry of the time source that is used as calibration reference. The special value 0 is used if the field is not set, and means that the node clock is used as reference.