Time needed for connecting from a domestic flight to an international flight

Time needed for connecting from a domestic flight to an international flight?
We booked a vacation with a travel agent and I just realized that the flights she booked us for only give us a 1 hr, 15 minute layover to connect from a domestic flight (O'Hare to Miami) to an international flight (Miami to Aruba). Is this going to be enough time to make that connection (assuming no delays)? Also, do you have to completely leave the security area and then reprocess through security/customs when arriving from a domestic flight and departing on an international flight?
Air Travel - 3 Answers
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1 :
Yes, you don't go through any customs checks. so the hour+ is more than enough time. You shouldn't have to go through security again.
2 :
Although you will not need to go through customs checks etc again, you will possibly need to make your way to a separate gate, and I would also confirm when you check-in at O'hare, that your baggage is checked through to Aruba.
3 :
It's enough time if you're traveling on the same airline. If not, and the other airline is not within the same concourse security area, you will need be re-screened. MIA s*cks for interline connections and I'd prefer more time ... btw "assuming no delays" is unrealistic. RJ