Ok I'll end my sarcasm here. This is one of the humorous cases ever. I've just installed my mtnl bb around 4 hours back and it had started giving me problems. Let me tell you that I've my own modem+ router which I used with airtel and it worked perfectly fine. So all of a sudden the internet light goes off and the dsl starts to blink slowly until the Internet light lights up again and running. It happens automatically and the Internet light takes about 1 min to restore.I have a parallel line and it doesn't cause a problem. And there's no disturbance on the line.