AutoPASS

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This article is about the electronic toll collection system in Norway. For the stored-value smart card in Singapore, see Autopass Card.

AutoPASS is an electronic toll collection system used in Norway. It allows collecting road tolls automatically from cars. It uses electronic radio transmitters and receivers operating at 5.8 GHz (MD5885) supplied by the Norwegian companies Q-Free and Fenrits.

1 Technology
2 Supporting toll plazas
3 See also
4 External links

[edit] Technology

The system involves the installation of a DSRC based radio transponder on the windscreen of a vehicle, and to sign an agreement with one of the toll collection companies in Norway. Tolls are charged at toll plazas as before, but cars can drive past in up to 80 km/h. The system is administrated by the Norwegian Public Roads Administration. 23 of the 45 toll roads in Norway use the system, in addition to tests for use of the system on some car ferries. The primary reason that some projects don't support AutoPASS is that they charge both for the car and for passengers, which the system cannot support. All projects using AutoPASS can only charge per car. All systems with Autopass also have manual payment methods, though not nessesarilly manned.

Each AutoPASS unit contains a microcontroller which will process requests from the road side, and respond with the proper information to the road side.

There are 5 generations of cryptographic key pairs inside each AutoPASS unit, which are unique for each unit. The cryptographic keys are used for authenticating the unit when passing a toll plaza, thus making it difficult to make fraudulent copies of a AutoPASS unit. Unlike similar DSRC based tolling systems used in many countries, there is no access control in the Norwegian system, the unique ID within the unit is available to be read for those who have the proper DSRC equipment.

There is an internal storage space for 100 log entries, which are normally updated each time a vehicle owner is charged when passing a toll plaza. This is a collection of receipt entries which includes the time, date and the station identity of the toll plaza which did the tolling transaction.

Each AutoPASS unit features a move detect mechanism. When the unit is removed from the windscreen, an electrical switch will be activated, causing a flag to be set in processor within the AutoPASS unit. This flag will be registered when doing a tolling transaction the next time the unit passes a toll plaza.