IT really depends how many facilities an airport has for international flights. Many airports have an "international" terminal where all foreign flights arrive by a US or foreign airline. Sometimes this is a section of a terminal or a separate teminal. AT MIA
which have so many international flights it all depends where the particular airlines facilities are. AT LAX
there are several FIS areas, it all depends which terminal your airline uses.
their are two areas used by foreign airlines, Terminal 2 and TBIT
have their own FIS facilites within their own terminals at LAX
many foreign airlnes use terminal 4, the IAB
replacement. Many also use terminals 1,3, 7 and 8. Terminals 2, 5 and 6( being demolished) are for domestic flights only.