Hi Veera,

It's not a stipend provided to all the Masters' student but only to a selected few under it's Teacher Assistantship Programme. Firstly, you need to be enrolled in the M.E programme (equivalent to M.Tech degree). The selection to that particular program is based on your marks in the first semester, that is, youracademic record as well as an interview. Only if you clear these two will you be eligible for the program and the consequent stipend which is equal to a sum of Rs.50,000 per semester. 

For more information, I advise you to go through the following link very carefully, it will be very helpful to you and give you a clearer picture of the Program and the process. 

Link- http://www.bitsadmission.com/hdmain.aspx?id=1262015

I hope this is useful. Please reach out to me for any further information or query.