JoSAA is a common portal for admission to NITs, IIITs, IITs, Government Funded Technical Institutes, etc. Single application and choice list has to be submitted for admission to any of this.

Till 2014, we had CSAB that was for admission to NITs, IIITs, etc. and there was separate portal for admission to IITs. Since 2015, both of them have been merged to make the entire process more easier and simpler.

Yes,one is supposed to apply on both the platforms but firstly we should know that Josaa counselling and csab counselling is not held parallely. After completion of all round of Josaa counselling csab conduct spot round counselling on remaining seat for Nit , Iiit and gfti. If you are already participated in Josaa counselling and didn't get a seat, you can definitely register for csab also

Both CSAB and JOSAA are different Counselling Procedures and CSAB is conducted only after the Last Round of JoSAA Counselling.

For more information about the difference between JoSAA and CSAB do follow the link below

https://dqxeclau.top/question-whats-the-difference-between-jossa-and-csab-is-one-supposed-to-apply-on-both-the-platforms

For more information about JoSAA 2021 do follow the link below

https://engineering.careers360.com/articles/josaa/amp