The Counselling and seat allotment of JEE Main 2017 will be conducted by Joint Seat Allocation Authority (JoSAA). JEE Main 2017 counselling and seat allotment will tentatively be conducted in 6 rounds.
The joint counselling and seat allotment of JEE Main 2017 will be conducted online, while registration (option entry), will tentatively start from the first week of July 2017.

To know about the same in detail you can go through the below article -

JEE Main Counselling & Seat Allotment 2017

Hope this helps!!!