The BSE benchmark index Sensex was up byover 116 points in the opening trade today.The 30-share barometer which had gained 29.63 in the previous session, added 116.29 points, or 0.63 per cent to 18,455 . The wide-based National Stock Exchange index Nifty moved up by 32.60 points, or 0.59 per cent, to 5,604.