Road Network Operations
& Intelligent Transport Systems
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Electronic payment (See Electronic Payment) is most commonly used for electronic tolling. Tolling can be for any number of purposes, although traditionally it was used to pay for the upkeep of various sections of road networks. Tolls are deployed on bridges (such as the Dartford Crossing, UK), tunnels and motorways (the M50 in Dublin, for example). Much of the money raised may be spent on maintenance. Some countries (particularly in mainland Europe) also toll the use of their motorway network to pay for its upkeep.

However, with the increasing level of complexity offered by technology the debate on road user charging has become more complicated. Charging can now be for specific purposes or policy objectives – road network maintenance, road space allocation, revenue generation, and the user/polluter pay principles (integrating societal and environmental costs in congestion and road user charging). Such systems can also be based on time, geographical location, type of vehicle or a combination of them.


Traditionally tolls were collected manually, requiring large amounts of space for toll plazas with their many lanes and booths - and causing major disruption to the flow of traffic. Developments in technology have enabled these to be largely replaced by less disruptive techniques – with vehicles being identified to the tolling authority by three different methods (on-board units, RFID tags, ANPR cameras) which can be used alone or in combination with each other.

On-Board Units (OBUs)

Microwave DSRCs (dedicated short-range communications) makes it possible for vehicles to be identified by a base station without their having to stop at a toll barrier, although some systems still only operate at low speeds. A programmed On-Board Unit (OBU), registered with the vehicle type and the operator’s details communicates with an electronic reader, enabling a single bill to be collated from regular trips, which are then invoiced directly to the company or driver. More recently, increasing numbers of OBUs and tolling systems track GPS data to measure how far the vehicle has travelled on any given toll operator’s roads. The development of toll roads across Europe has not been well co-ordinated so far, leading to some international transport companies having to install up to five different systems on board each vehicle. Examples include the M6 Toll in the UK, the LKW Maut in Germany (See LKW Maut Electronic Tolling (Germany)), the French ECOTAXE and Malaysia’s ‘PLUS’ Toll.



As with asset tracking (See Security), terminal processing (See Terminal Processing) and end-to-end tracking (See End-to-End Asset Tracking) the development of RFID tags has changed the face of toll collection. Here, at the entrance and exit points of the tolled area, a passive RFID tag – embedded with the vehicle and operator’s details – is scanned by a dedicated gantry and the details passed to a central server where the bills are created, collated and sent on to the vehicle operator. Examples include the Dubai ‘SALIK’ System and the Singapore ‘ERP’ System.

ANPR Cameras

ANPR cameras can either be used as stand-alone systems (as in the London Congestion Charge) or as an additional level of security for the OBU or RFID systems. This is especially useful to track and charge users who do not have RFID tags or OBUs fitted (tourists or irregular users of the road) or where the OBU or RFID tag has become damaged and is no longer operational. Once scanned by ANPR, the number plate can be cross-checked with the vehicle owner’s database and a bill despatched. Alternatively, users can submit payment by telephone, internet or at a kiosk by stating their number plate, allowing payment to be processed after its registration.


Lack of interoperability of equipment and back office systems between tolling authorities is a key barrier to their deployment and realising the full benefits of their potential – particularly with regard to OBUs. Poland, for example, has different operators for its major motorways, which has resulted in the need for users of the equipment to purchase multiple transponders. The European Union has been trying to achieve harmonisation through open standards and common guidelines on deployment given the large amounts of international road freight that crosses borders every day. Progress is slow.

GPS based systems require very high-detail position and mapping tools to ensure that, where two roads run parallel (an old main road and a new motorway for example), the correct location of a vehicle (and the charge for road use) can be calculated accurately. This sort of tracking has associated issues such as privacy and control of information.

For emerging economies, interoperability is the key issue, to break down barriers in the seamless movement of goods. As such, satellite based systems are often seen as preferable, although the issues of accuracy of mapping remains a challenge. (See Case Study ‘LKW Maut (Germany))

Theft of on board units is also a concern. Malaysia, for example, has seen significant numbers of crimes with SmartTAG transponders being stolen.

Reference sources

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