Japan’s telecommunications giant Nippon Telegraph and Telephone Corp. said Monday it will reorganize its business structure by consolidating its overseas operations in October under a subsidiary NTT Data Corp. to enhance its competitiveness in the area of digitalization. NTT Inc., NTT’s wholly owned unit and a holding company of its overseas operations, will take over NTT Data’s businesses abroad. NTT Data will control NTT Inc. by acquiring a 55 percent stake. Businesses currently under NTT Inc. include South African IT service firm Dimension Data. NTT Data will also transfer its domestic busi…