I will be flying though Atlanta ATL from a domidtic city then onto Punta Cana, Dominica Republic PUJ.

I'm just over-preparing because our layover is a bit tight, 1 hour and 2 minutes.

Looks like I will fly into concourse (edited, I typed gate) B. Okay, no worries. But it says I'm flying out of gate I. On a map I found I see concourse A through F but no I.

♦Where is gate I?

♦Will I need to go though any special extra security to get from concourse B to I?

Thank you.