For all those bashing govt for FUP (Fair Usage Policy), just wanted to inform that govt organisation has nothing to do with FUP. Every company worldwide has FUP.
When I had Sky broadband in UK with unlimited 4 Mbps connection, they also had FUP, only that limit was very high, perhaps 40-50 GB. Beside postpaid mobile connection which I had, was having unlimited calls to landline, but condition was that call must not be more then 1 hour. If call duration exceeds 1 hour, they start charging. They recommended to diconnect call at 59 minute and redial again. I felt it strange (and stupid), but anyways it was their FUP rule for unlimited landline call.
About BSNL as well, having FUP is not issue, but limit should be much higher ~20 GB should be good limit instead of ridiculous 1 GB limit.