[Android Central Question]

What is best plan for existing broad band subscriber

[belodion]

The one that meets your requirements, or comes closest to that. Consider the download speed, the data cap if any, and the telephone charges. In my own case for example, the basic 17 megabits per second service is perfectly adequate; unlimited data usage, not because I use huge amounts but because I don't want to have to think about that; and no inclusive telephone calls, because I almost never use the line for telephony. Some providers offer such a package, others not.
Consider all those things, and of course at a price agreeable to you, and if necessary, be prepared to change provider.