e-TAG is an electronic toll collection

Electronic toll collection

Electronic toll collection , an adaptation of military "identification friend or foe" technology, aims to eliminate the delay on toll roads by collecting tolls electronically. It is thus a technological implementation of a road pricing concept...

 system used on tollways throughout Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

. Based upon the DSRC protocol, it was originally developed by Transurban

Transurban

Transurban is an international toll road developer and manager with interests in Australia and North America. In Australia, Transurban has a stake in five out of Sydney’s nine motorways, and in Melbourne it is the full owner of CityLink, which connects three of the city’s major freeways...

 for use on their CityLink

CityLink

CityLink is a system of tolled urban Highways in Melbourne, Victoria, Australia. The company Transurban was awarded the contract to augment two existing freeways and construct two new Toll roads—labelled the Western and Southern Links—directly linking a number of existing freeways to...

 tollway in the early 1990s, with the system since adopted by all electronic tolled roads, bridges and tunnels in Australia. At the present time there are over 850,000 e-TAG account customers and over 1 million e-TAGs issued. In early 2009, the Sydney Harbour Bridge

Sydney Harbour Bridge

The Sydney Harbour Bridge is a steel through arch bridge across Sydney Harbour that carries rail, vehicular, bicycle and pedestrian traffic between the Sydney central business district and the North Shore. The dramatic view of the bridge, the harbour, and the nearby Sydney Opera House is an iconic...

 became toll-booth free, meaning that you must use an eTag to cross the bridge.

Technology

The e-TAG tolling is based on a modified IFF

Identification friend or foe

In telecommunications, identification, friend or foe is an identification system designed for command and control. It is a system that enables military and national interrogation systems to identify aircraft, vehicles, or forces as friendly and to determine their bearing and range from the...

system.

Official site

• Roam Tolling Pty Ltd
• Transurban Group (Parent Company)