The BSE benchmark Sensex rose by over 105 points in early trade today on buying by funds and retail investors at existing lower levels amid a firming trend in Asian markets.The 30-share barometer, which lost about 76 points in the previous two sessions, recovered by 105.15 points, or 0.61 per cent, to 17,235.82.Similarly, the wide-based National Stock Exchange index Nifty moved up by nearly 34 points, to 5,222.85.