DSA stands for Doncaster Sheffield Airport, while JFK stands for New York John F Kennedy Intl Airport. These codes are often called IATA codes, a set of identifiers established by IATA (International Air Transport Association) that is widely used by airlines and the aviation industry. Newark Airport (EWR), New York LaGuardia Airport (LGA), Buffalo Airport (BUF), Syracuse Hancock Intl Airport (SYR), Rochester Greater Rochester Intl Airport (ROC) are some additional IATA codes for airports related to your trip.