Dear Aspirant,

The very fact that a 3 year diploma gives you eligibility to get a lateral entry to a B.E or B.Tech course shows that it is a recognized medium of study provided it is from an approved College. Yes you can qualify for the JEE with your diploma and NOIS +2.  It is good that you are also doing you distance study for your +2, this is very important as your PCM standard in the +2 is much higher than in the Diploma courses.  We think you are preparing very well and if you later join a coaching center than it will give you the necessary guidance to succeed.

Good Luck