Columbia subject headings:
Harvard subject headings:
Highway communications--Security measures--United States.
Highway communications--United States.
Information technology--Security measures--United States.
Intelligent Transportation Systems--Security measures.
Intelligent transportation systems--Security measures--United States.
Transportation--Technological innovations--United States.
Princeton subject headings:
Highway communications--Security measures--United States.
Information technology--Security measures--United States.
Intelligent transportation systems--Security measures--United States.