As far as I know, you have to follow the same steps at any port of entry if US is your final destination. 1. clear immigration 2. claim baggage 3. clear customs 4. re-checkin baggage (this depends - sometimes the officials will simply put it back on the belt for recheckin, and at other times you have to lug the baggage to the respective airline for rechecking in) 5. proceed to the correct terminal for the next leg of your voyage. All these are done at single entry point aka port of entry. After that your flights are considered domestic. Hope it helps