hello mr raval , as i tried to solve the problem with different methods , i found a way to stop the drop in line , it is not bsnls problem , it is the ppoe mode that is the problem in the modem we got , i worked fine for 4-5 months in always on mode , but after 4-5 months it started showing this problem , at last after so much time , i tried the bridge mode with the dialer on the desktop and i found that there is no disconnection in the line and i have downloaded around 4.4gb daily for the past one week , i think you shud change from always on mode to bridge mode , it is working great for me, the only probem is that you have to wake up atleast once to start the connection else everything is fine there is no sudden drop in the line . try it , it works for sure . best of luck