On a daily basis, it is estimated that 30% of vehicles on the road in the downtown area of major cities are
cruising for a parking spot and it takes an average of 7.8 minutes to find one [1]. This causes not only a waste of
time and fuel for drivers looking for parking, but it also contributes to additional waste of time and fuel for other
drivers as a result of traffic congestion. For example, it has been reported [2] that over one year in a small Los
Angeles business district, cars cruising for parking created the equivalent of 38 trips around the world, burning
47,000 gallons of gasoline and producing 730 tons of carbon dioxide.
Over the past two decades, traffic authorities in many cities are building so-called Parking Guidance and
Information (PGI) systems for better parking management. PGI systems present drivers with dynamic
information on parking within controlled areas and direct them to vacant parking spots. Parking information may