The Polish Research Project of NATCS

Vehicle Engineering (VE) Volume 1 Issue 4, December 2013

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The Polish Research Project of NATCS Gabriel Nowacki*1, Anna Niedzicka2, Ewa Smoczyńska3 Military University of Technology, Cybernetics Faculty Sylwester Kaliski 2, 00-908 Warsaw, Poland

*1

Motor Transport Institute, Transport Management and Telematics Centre Jagiellońska 80, 03-301 Warsaw, Poland

2, 3

*1

gnowacki@wat.edu.pl; 2anna.niedzicka@its.waw.pl; 3ewa.smoczynska@its.waw.pl

Abstract

(Cerny K. 2008; Kossak A. 2009).

The paper discussed assumptions and test results of NATCS Pilot Project developed by Motor Transport Institute, Autoguard SA, and Fela Management AG. Legislation steps were taken at the EC level because of interoperability problems of European Electronic Tolling Service (EETS) in EU. Commission has urged member states to conduct studies and pilot projects concerning these issues. Motor Transport Institute has taken up a challenge by developing and testing the pilot project–the functional structure of the NATCS. System has some requirements of EC legislation and it is interoperable with other DSRC and GPS/GSM based systems implemented in member states of the European Union. Test results have shown a high accuracy and efficacy of the system.

In addition, data transmission is done using wired communications, and then it can take place over the Internet. The DSRC system will not be able to be incorporated into an integrated technology platform, as it will not even be able to collaborate with other national transport systems. Even in the case of the DSRC system, which is provided by Kapsch, each country has a different type of OBU device. Another solution is to apply GSM or GPS systems.

Keywords National Automatic Toll Collection System (NATCS); Laboratory Model of Toll Centre (LMTC); Interoperability

Introduction There are two different types of European Electronic Tolling Service (EETS): Dedicated Short Range Communication (DSRC) and GPS/GSM based systems.

In most EU countries (Austria, France, Spain and Italy) DSRC type systems of electronic tolling are used that rely on dedicated short range radio (microwave frequency – 5.8 GHz).

The OBU on-board device, operating in the DSRC system is small (size similar to a packet of cigarettes).

It is mounted on the windscreen inside the vehicle.

However, the device is not very smart, very simple and only performs validation functions (read only), and it has no display, and cannot receive or transmit any message. The DSRC system requires a well developed road infrastructure, at every crossroads, and gates it must be installed at entrances and exists.

In the DSRC system, there are two types gates: communication Toll Gates and control gates, because their number is ten times greater than in the GPS/GSM

In this system, thanks to the GPS satellite positioning virtual control and tolling points established, the system can operate without the use of control gates.

Data are transferred to the system directly from the OBU devices, using GSM communications.

According to European Commission electronic tolling systems used in European Union are not interoperable for the following reasons: differences in the concepts of tolling, technology standards, classifications, rates, discrepancies in the interpretation of laws.

European Commission has taken two mile steps in this regard. The first was Directive 2004/52/EC of 29 April 2004 on the interoperability of electronic road toll systems in the Community. Then there was the decision of European Commission on 6 October 2009 on definition of European Electronic Toll Service (EETS), and system architecture.

According to European Commission decision 2009/ 750/EC, European Electronic Toll Service (EETS) should enable road users to easily pay tolls throughout the whole European Union (EU) thanks to one subscription contract with one Toll Service Provider and one single on-board unit (OBU).

The mentioned decision was supported by standard EN ISO 12855 (CEN, Brussels, 05.02.2010)–tolling interoperability aims at enabling a vehicle to driver trough various Toll Domains while having only one OBU operating under contract with Toll Service

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Provider.

Implementation of interoperability is a long-term and precise action. What comes to the fore in the implementation strategy for interoperability is the need for introduction of the EETS system, consisting of the following systems: DSRC, GSM, GNSS 1.

Interoperability with Austria TOLL2GO is a joint service provided by Toll Collect and ASFINAG, the toll system operator in Austria. Launched on 1st September 2011, TOLL2GO makes it possible to use the Toll Collect On-Board Unit to pay truck toll charges in Austria for heavy goods vehicles weighing 12 tonnes or more. The service is especially convenient for freight transport companies with vehicles that are frequently on the road in Austria and Germany 2.

TOLL2GO represents a further step toward a crosssystem, transnational toll service. Now, for the first time, interoperability has been established between a microwave-based and a satellite-supported toll system.

The advantage for toll system customers who use the new TOLL2GO service is that they only need one invehicle unit–the Toll Collect OBU–to pay toll charges in both countries. The TOLL2GO service is free of charge for current Toll Collect and ASFINAG customers. For new customers (those who apply for an initial contract), ASFINAG charges a on-off processing fee of EUR 5.00.

Although only one On-Board Unit is used, customers still have separate contracts with each of the two toll operators. As in the past, toll invoicing by the two companies remained completely separate.

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structure, which consists of the following elements: 

Intelligent on-board device called TRIPON-EU, which was installed in test vehicles,



OBU device installation system using a chip card,



two control gates (with DSRC modem and a vision tolling system),



laboratory model of national Centre for automatic tolling NATCS,



a proxy server for data exchange between headquarters and the OBU system via GPRS,



control centre to manage the OBU devices allowing for management of OBU and analyses of data related to the collection of tolls,



analytical tools for DSRC, image analysis and classification of vehicles.

The design of the system included the following technologies: 

satellite positioning via GPS, and Galileo in the future,



wireless communication via GSM (TS 03.60/ 23.060),



dedicated short range communications – DSRC (5.8 GHz).

The architecture of the system is in conformity with Directive 2004/52/EC and decision of the European Commission of 6th November 2009 as well as the CE and ISO standards (Fig. 1).

Based on mentioned analyses, the best universal solution in complicated situation in UE is implementation of hybrid system (includes: DSRC, GSM, GPS technology), the TOLL2GO is this kind of system, and NATCS is mentioned type of system.

Characterisation of NATCS Functional Structure of NATCS The research team identified NATCS’s functional GNSS-Global Navigation Satellite System. GNSS-1 is based on existing segments of the orbit Navstar GPS and Russian GLONASS system. An integral part of the GNSS-1 is a system of differential (DGPS-Differential Global Positioning System). Development of GNSS-1 will be the GNSS-2. The constellation of navigation satellites will include the GPS Navstar satellites of II F type GLONASS M and new European satellites wit working name of Galileo.

2 http://www.toll-collect.de/en/all-about-the-toll/toll2go.html.

1

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FIG. 1 RESEARCH TEAM AND ELEMENTS OF THE SYSTEM

During the tested four OBU units were examined, whose task was to detect all events associated with the collection of toll directly in OBU, as well as in the log file and display them on the screen. OBU is also meant to send log files to the proxy server and receive data from the server (data, status information and software updates.)

Test route includes as follows:

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

Two segments of expressway S7 (planned route Gdańsk – Rabka with total length of 720 km): eastern bypass of Płońsk, western bypass of Nowy Dwór Mazowiecki (a section of 14,6 km, Zakroczym – Ostrzykowizna – Czosnów),



One segment of expressway S17 (planned road on the Warsaw – Hrebenne route): bypass of Garwolin of 12,8 km length with two carriageways (each with two lanes and a 2,5 m wide emergency lane and a 4 m wide median strip.

Characteristics of OBU The onboard device TRIPON-EU is available in two different versions. The test system used the version mounted in a single casing collecting all components, including GPS and GSM antennas. This version is designed for installation on the windscreen of the vehicle.

Tripon EU (Fig. 2) independently analyses the data (GPS location data, vehicle defined data, data on tariffs -fixed schedule of fees and other data) that are remotely transmitted, in real time, to the server.

FIG. 2 OBU– LEFT: GENERAL VIEW, RIGHT: DISPLAY

Data about events related to billing, and events related to the control and supervision, are limited to a minimum, which significantly increases the throughput of the system and reduces the operating costs.

Depending on the required precision and an additional control, Tripon EU can operate in two positioning modes: using signals from GPS and assisted by a signal trace from other onboard equipment.

In order to verify system capabilities in both vehicles OBU devices were checked using only the GPS signal and in conjunction with an additional device, from which passage signal was received. The comparison indicated a small discrepancy between the satellite positioning signal and the passage signal, indicating these by "Delta Tacho +-x%" messages.

OBU uses built-in GSM antennas, and there is no need for external antennas. The SIM card installed inside cannot be replaced by the user. For the convenience of testing, using the S button (send) one may activate a

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GPRS communication session at any time without having to wait for the next automatically initiated session. The onboard device can receive short text messages. These text messages can be displayed on the tab (Fig. 3) in the text message window.

FIG. 3 ONBOARD UNITS OBU – SMS

Each received message can be: confirmed, denied, confirmed by way of a predetermined message or deleted by the driver.

For this purpose, appropriate options in the menu are provided. This functionality has been included to easily demonstrate the potentially available value added services that can be implemented on the platform OBU. OBU is equipped with a DSRC module (5.8 GHz, IR) DSRC (Dedicated Short-Range Communications). In cross-border traffic, OBU device enables collaboration with GPS/GSM tolling systems (Germany, Slovakia) or DSRC systems used in other countries (Austria, Czech Republic, Italy, Spain, France). The basic standard used in these types of systems (DSRC) is the ISO EN 15509 standard (Media Transactions). The onboard unit makes use of such transactions in order to illustrate the possibility of tolling in cooperation with the vision system - ANPR. Transactions can be configured in such manner, as to support DSRC attributes that are necessary in a specified tolling implementation.

Each onboard unit OBU is equipped with a Smart Card interface, which can be used for calibration and initialisation purposes. When configuring the test system, Smart Cards will be used for: initiating onboard units with contract data, configuring parameters of onboard equipment, all operations with the use of cards can also be initiated via the GSM link.

OBU can be configured to operate as a less or more "intelligent" unit. For the purposes of technical tests in Poland, the “more intelligent” mode of the device was selected. In this mode, all the events connected with the collection of tolls were detected in the onboard device and recorded in an event file.

From time to time, the event file is transmitted via GPRS channel to proxy server. For validation 73

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purposes, data from the proxy server are exported in Excel or XML format. A controlling application of OBU onboard units - Control Centre provides access to data from any Web browser. Such access is only available to authorised users with an appropriate account (username, password). Accounts were made available to Autoguard company and the Motor Institute Transport for the entire testing period.

In order to conduct in-depth analysis, the onboard units were configured in such a way as to ensure that (essentially) raw GPS positions are transmitted to the server. In this way, the analysis involves both the file of events, as well as the raw GPS positions.

The OBU device should store the following data: vehicle class, vehicle weight, axles or class of emission, registration numbers and contractual details. Data can be entered into the device using a chip card.

The GPS module used in OBU devices supports computing navigation (DR, dead reckoning) to improve the accuracy of positioning.

GPS data (from satellites), supplemented by the results of computing navigation are used as input for detection of on-ground facilities. Detected events are logged in the event file. The European EGNOS system can be enabled or disabled through the configuration file activated at the time of start-up. The device was designed to cooperate with Galileo.

Data recorded by the OBU onboard unit were transmitted to the internal components of the EETS system, using GPRS technology (packet data transmission system used in GSM technology).

The data transmission between the mobile onboard units and the internal elements of the system takes place via a proxy server, which operates completely independently of the billing and accounting system.

Data is transferred in batches, which means that one does not need to maintain a permanent connection between onboard devices and the internal components of the system. This is one of the biggest advantages of the concept of smart clients. GPRS allows for even greater reduction of communications costs.

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onboard units with contract data, configuring parameters of onboard equipment, all operations with the use of cards can also be initiated via the GSM link.

Toll Controll Gates The concept of toll control gates in the system tested in Poland is based on experiences Fela company, collected during the operation of the Swiss system.

The following devices are installed on control gates): 

DSRC locator to carry out transactions with the traffic lane controller (according to EN 15509 standard),



vision system ANPR (automatic number plate recognition and photographic documentation (ANPR, only from the front) a local driver software for the registration fee collection.

The DSRC locator conducts standard DSRC transactions (in accordance with CEN TC278/EN155509) detecting every vehicle passing through the gate.

Essentially, the contract data are recorded, including registration numbers and characteristics of the vehicle.

The data collected should include in particular: the registration number and characteristics of the vehicle.

These data are essential in the process of collection of fees – i.e. they are compared with the data coming from the ANPR (automatic number plate recognition).

The DSRC locator is mounted on the top of the gate, about 5-6 m above the road. In addition to the beacon, a so called “traffic lane driver software” should be installed on the gate, which will process data from the locator and control its operation during the transaction.

The data should be periodically sent via Ethernet to the system’s central unit.

Transactions can be configured in such manner, as to support DSRC attributes that are necessary in a pecified tolling implementation.

Depending on the location of gates and/or traffic conditions, one can apply a variety of other triggering signals. The monochromatic ANPR camera will be equipped with an image converter with a resolution of 1620 x 1220 pixels and Gig-E interface. The controller installed inside the camera casing: transmits triggering signals to the camera/impulse source of infrared radiation, converts the signals from light sensor, based on signals from the light sensor generates the parameter settings of the camera/impulse source, controls the temperature in the camera casing (turn on/turn off the heating/cooling).

Each onboard unit is equipped with a Smart Card interface, which can be used for calibration and initialisation purposes. When configuring the test system Smart Cards will be used for: initiating

A photo of vehicle is transmitted to tolling server from a given traffic lane for further processing and is analysed in order to read the registration numbers. At the same time, it will serve as documentation if it is

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necessary to start tolling procedures.

interface.

To enable fully automatic gate operation, an ambient light sensor is used, whose signal is based on the control of the camera and the impulse infrared radiation source. The sensor is oriented on the detection of vehicles and has a dynamic range from 3 to 30,000 lux.

GNSS Interface (GPS – Galileo). This interface is installed and can not be altered in any way. The onboard units record (in files) every instance of losing of GPS signal for more than a specified period of time.

All data collected at toll control are transmitted to tolling system servers and are made available in the tolling controlling software.

This software enables viewing all collected images, results/details of ANPR algorithm operations and DSRC results.

Laboratory Model of Toll Centre Laboratory Model of Toll Centre (LMTC) comprises of the following elements: 

Three PCs – one dedicated as a database server, the second one serves as application software server, while the third one is a user terminal,



application and system software,



databases,



software and physical interfaces (between NATCS and OBU, between NATCS and control gates),



user interface ((online WWW service).

In the proposed solution, the proxy server is the main element of the service provider’s interface. It supports and controls OBU’s sending and receiving of all data.

The system operates using Linux and ensures stable operation.

The task of the proxy server should include communication only, as well as SW updates of OBU devices. Toll tariff tables and geographic objects displayed on OBU’s screen should be sent from a proxy server to the OBU. Data received from the OBU should be checked for consistency, and then made available for analysis.

Databases in NATCS are divided into the following groups: data on users, vehicles and tariffs, Physical Inventory, Dynamic Inventory.

Characteristics of Interfaces The pilot project is focused on interfaces associated with the road and external elements of the system operated by the user. Road related interfaces include (depending on the requirements of the system): GNSS interface (GPS, Galileo), CN interface (GSM), DSRC

DSRC Interface. DSRC interface) 5,8 GHZ, IR) is fully compatible with the newest CEN DSRC standards.

DSRC Interface for tolling transactions. Such transactions make use of the model compatible with the EN 15509 tolling data transmission standard. This model was used in the test system. Currently, European Union is working on a new interface standard for the general tolling interface, in particular including GNSS solutions (ISO 13813).

DSRC Interface for auxiliary locators. In critical areas, it is GPS, or where GPS positioning accuracy is inadequate, the situation can greatly be enhanced by the auxiliary locators (augmentation beacons). Augmentation beacons provided by FELA are powered by photovoltaic cells.

Augmentation beacons operate based on the same DSRC protocol as that specified in the abovementioned standards.

There is a one-way communication (from the locator to the onboard device) and takes the form directionless broadcasted messages. This is how each locator transmits information about its location. The form of this information is identical to the form of position data from GPS receiver, or it is information directly identifying the toll due at that point of collection (which is most effective). European Union is currently developing standards for DSRC broadcast transactions.

The test system does not provide utilisation of augmentation beacons.

GSM Interfaces. In the modern electronic tolling systems, key role is played by interfaces utilising GSM data communication.

GSM interface for onboard devices. This interface used to exchange data with onboard equipment. Normally, OBU must communicate once a day to transmit the log file to the internal components of the tolling system and to download software updates. If necessary communication sessions can be initiated more frequently, in the test system they were initiated every 4 hours or on demand. Each time the onboard device connects to the proxy server, it checks if there are any new updates and if that is the case, it downloads them immediately. This interface was built into the test system.

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GSM interface for tolling. Data from mobile and portable tolling devices can be transferred to the internal components of the system (EFBO, Enforcement Back Office) via GSM links. In the case of fixed gates, however, it is recommended that instead of GSM links wired connections be used (due to costs, stability, bandwidth). In the test system tolling data were broadcasted over the Internet GSM Interface for augmentation beacons. Augmentation beacons must communicate with internal components of the system to configure and control their condition.

For such purposes, the GSM interface is perfect. What is necessary here, is transfer of small amounts of data.

Thanks to GSM connection augmentation beacons can be located virtually anywhere without any restriction.

Test Results of NATCS General Information of Test Tests of NATCS including control of OBU devices, tolling segments at selected sections of roads as well as control gates were conducted in July and August, while vehicles passing through the control gates were registered from 1st July to 30th November 2010.

The architecture of the system is in conformity with Directive 2004/52/EC and decision of the European Commission of 6th November 2009 as well as the CE and ISO standards.

During the test, four OBU Tripon EU units were examined, whose task was to detect all events associated with the collection of toll directly in OBU, as well as in the log file and display them on the screen. OBU is also meant to send log files to the proxy server and receive data from the server (data, status information and software updates.) For testing purposes, four vehicles were added to the database: Volkswagen Golf – research vehicle of Autoguard, reg. no. WF 93311; Fiat Ducato, vehicle of Autoguard SA, reg. no. WF 4244E, total weight 1 968 kg, number of axles – 2; Volkswagen Crafter, vehicle of Autoguard SA, reg. no. WF 1831E, total weight 3 508 kg, number of axles – 2; Volkswagen Transporter, research vehicle of ITS (Motor Transport Institute), reg. no. WH 15904, No of axles – 2.

Out of the several proposed test route options, we chose the Płońsk - Garwolin, Garwolin – Płońsk route, as the most diverse one that allows checking the greatest number of elements of the system, including in the immediate vicinity of the route the both control gates and allowing the use of as many as three actual 76

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segments of expressways: 

two segments of expressway S7, eastern bypass of Płońsk (a section of 4,7 km), western bypass of Nowy Dwór Mazowiecki (a section of 14,6 km, Zakroczym – Ostrzykowizna – Czosnów),



one segment of expressway S17, bypass of Garwolin of 12,8 km length with two carriageways,



two segments of National Roads.

On the basis of recorded data, transmitted by the vehicle in the form of messages, it was possible to recreate the exact route of the vehicle with the OBU device.

Position Dilution of Precision One of the most important parameters determining the accuracy of measurement and transmitted in location messages is PDOP (Position Dilution of Precision)-defect in determination of position precision.

PDOP is a coefficient describing the relationship between the error of user’s position and the error of satellite position.

The following descriptions signal quality depending on the value of PDOP are assumed: 1 (perfect), 2–3 (excellent), 4–6 (good), 7–8 (moderate), 9–20 (poor), > 20 (bad).

For the purposes of NATCS, it was assumed that value of PDOP should be 90 percent of excellent (between 0.1 and 3), for more accurate calculations of position.

The presented graphs (Fig. 4) show that the tested OBU with the number of measurements are respectively 90%, of perfect values, and 8% excellent values. The number of results in the category of poor results (PDOP 9,9 - 2%) exactly matches that corresponding to the absence of visible satellites.

FIG. 4 DISTRIBUTION OF PDOP FOR ALL OBU

The number of satellites used for measurements of all OBU devices is presented in Fig. 5. For the purposes of NATCS, it was assumed that GPS receiver in OBU should track at least 5 satellites, for more accurate calculations and in the event of the loss of signal from

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one of them.

FIG. 5 NUMBER OF GPS SATELLITES USED FOR LOCATION MEASUREMENT

The presented data showed that the maximum number of satellites used in for the purpose of location is 11, and in the case of 99% of measurements at least 5 satellitesare used (the detailed results of satellites: 5– 10%, 6–17%, 7–25%, 8–22%, 9–16%, 10–7%, 11–2%).

Registration Parameters of Gantries and LMTC As part of the project, two DSRC gates with tolling system were prepared. This has allowed for testing of the following functions: •

operation of DSRC microwave devices

•

operation of visual system ANPR system (automatic number plate recognition).

Data obtained from the passage of vehicles through the gates was stored in a separate database. Gates used for testing were described as follows: •

ITS Demo (UID=1000, 2),

•

Autoguard Demo (UID=1001,3).

From 1st July to 30th November 2010, 2964 vehicles passing through control gates were registered n the database of the system. Not all vehicles were equipped with OBU. During the tests at the ITS Demo and Autoguard Demo gates, using the DRSC system, passage of 24 test vehicles was recorded. During the tests at the ITS Demo gate as many as 667 photographs of passing vehicles were taken.

During the tests at the Autoguard Demo gate 2297 photographs of passing vehicles were taken. The registered vehicle was equipped with a French made OBU device - Passango (DSRC). It was fully identified in the system as a user, which means that the NATCS system is interoperable and can work with both, systems of DSRC type as well as GPS/GSM systems.

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devices were replaced with new ones. Due to a mistake, the devices were wrongly installed, however, the system immediately discovered the error.

Also the operation of the control gates was tested – mainly with respect to the detection of various vehicle speeds. Thanks to this, it was possible to adjust the software and then to check the newly replaced onboard OBU devices with respect to the correctness of detection of vehicles coming up to the control gate at especially small selected speeds. The system detects vehicles travelling at speeds of 1 to 200 km/h.

In addition to test the drives and the checking of the functionality of the, the efficacy of the gates was checked, recording all vehicles passing at the premises of Motor Transport Institute and at the premises of the AutoGuard company in various weather conditions and at various times of day.

The efficacy of automatic detection of number plates was 99,9%. All the segments were identified correctly by the onboard devices, and there were no problems in this respect. Each segment consisted of three points, and in order for each one of them to count, all three segments had to be detected by the OBU device. As a result of this drivers who will cut through toll roads, or only pass through them, will not be registered in the system.

The tests were successful and confirmed the efficacy of the selected solutions in accordance with the assumptions of the project.

Security aspects of NATCS General Information of Security Electronic tolling systems process sensitive personal data, vehicle traffic data and financial transfers.

Therefore, safety aspects are very important. Many standard interfaces such as GSM or WAN/Internet offer a variety of security mechanisms (e.g. secure https protocols) and one should make use of them.

During each and every passage, the operation of control gates as well as the conformity of the DSRC data with the ANPR (automatic number plate recognition) reading was verified.

The basic problem is to secure some data reported in the tolling process on the entire route of transmission (end to end). In other words, data generated at the beginning of the communication channel (e.g. onboard OBU device) delivered to the destination through various intermediate links and media should be fully protected during transmission regardless of any applicable security mechanisms used in the individual links / media.

For the purpose of the second stage, the onboard OBU

Each

interface

can

use

for

standard

security

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mechanisms: separate security mechanisms in GSM links, separate mechanisms in DSRC, and separate ones in the case of Internet connections. These mechanisms ensure secure transmission of data over a specific interface, and are important in the case of many top-level interfaces, such as those used in the internal system components.

The security of the whole system must be based on separate mechanisms to protect data transmitted by the various links and media throughout the entire route of transmission-from the source right to the place of destination. They should be independent of any security mechanisms used in the interfaces. Such end-to-end security mechanisms must be specifically appropriate for a particular system. For this purpose, the FELA company uses a standard infrastructure for public encryption keys (Kallweit T. 2010). This concept was tested in Switzerland, in the implemented tolling system for heavy vehicles, in which a dedicated and secure Certification Authority - CA. The use of end-to-end security. It is based on standard RSA encryption algorithms, using pairs of public/ private key and security certificates. Such security features allow for safe transmission of secure data to any destination.

Some processes are to some extent critical, e.g. generation of specific encryption keys such as DSRC Master Key. Access to the Certification Authority must be fully secured and controlled so as to obtain only certain trusted people.

Security Undertakings Security was achieved through undertakings (Kallweit T. 2010):

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the

following



The Certification Authority has generated a DSRC Master Key, used to start the system up.



Through certificates, each element of the system received from the Certification Authority a PupKey and a DSRC start-up key.

They were delivered to the individual elements, or otherwise these elements downloaded their certificates via the Internet.



The manufacturer the OBU onboard units installed a public key of the Certification Authority (CA PubKey) in each and every OBU device as well as a unique DSRC key.



The Proxy server/internal elements of the system received CA certificates, Proxy certificate, private keys and a DSRC Master Key. This operation was secured: the transfer of these

keys usually takes place via special Smart Cards. 

Internal elements of the system distribute the DSRC Master Keys to all DSRC locators. Upon start-up of the security system, the DSRC Master Key for all onboard OBU devices was updated via a secure communication channel with the internal elements. Thanks to this, the use of the initial DSRC key by the manufacturer of the OBU device is not associated with any excessive risk as the key will be replaced as soon as the device establishes communication with the internal elements of the system.



Upon receipt of the CA certificate with the CA public key, each element of the system generates its own pair of public/private key and sends its public key back to the internal elements of the system. From now on, all communication is secure (end-to-end security)

Change or Adding of New Keys to DRSC Master Keys DSRC Master Key is a 3DES encryption key used in wireless DSRC communication. To enable establishing of secure communication, each onboard OBU device must be equipped with an individual DES key, generated based on the primary 3DES Master Key. Each and every DSRC locator OBU onboard device is equipped by its manufacturer with a standard key used during the start up of the system. Once the device has established a secure encrypted communication according to RSA standard, the internal elements of the system will provide it with an individual key.

Normally, DES keys are customised by adding the serial number of the OBU device. Thanks to this, the initialisation process and the activation of the OBU device does not pose a major threat, as it does not require the transmission of data necessary to generate individual DES keys in a communication session with the internal elements of the system. Then individual DES keys can then be transferred via a GSM connection at the earliest possible opportunity.

Another important aspect here is that such a mechanism is necessary anyway in the case of replacement of DSRC key (e.g. if a given onboard device must be configured in another tolling system which does not utilise the DSRC technique.

Secure Activation Process of Onboard Equipment During activation at the point of service (POS) or workshop, onboard OBU device generates/activates,

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its pair of keys (private/public), transmits the public key to the internal circuits of the system. The safest procedure is to sign the transmitted OBU public key with a private POS or workshop key. With this solution, no user will be able to transmit a fake OBU key without the assistance of a certified POS or a workshop. Such a solution will make it very difficult for potential hackers to pose as members establishing connection with the internal elements of the systems via protected channels, because in the case of fraud, identification of a certified partner who assisted in getting a false key, would be quite simple and that partner would not be able to deny this. In addition to the cryptographic mechanisms, security of the system is ensured by other means, e.g. registration of unique IDs, SIM card numbers and other data relating to OBU devices. These data provided by the manufacturers was registered before the release of the onboard devices to users. Such registration allows the verification of reporting OBU onboard devices via internal elements of the tolling system.

Conclusions During the test of NATCS phase, from 1st July till 30th November 2010, 2964 vehicles passing through control gates were registered in the database of the system. In addition to testing the drives and checking the functionality, the efficacy of the gates was checked, recording all vehicles passing at the premises of Motor Transport Institute and at the premises of the AutoGuard company in various weather conditions and at various times of day.

The functional structure of NATCS was according to directive 2004/52/EC, decision of European Commission from 6-th October 2009 and CEN standards.

The efficacy of automatic detection of number plates was 98%, and thanks to proceeding data by analyzing stand, the efficacy of the system increased to 99.9%.

Analysis of the measurement data of the PDOP parameter and the number of satellites used during the test showed that 90% of the PDOP measurements were lower than 1, and 8% had value from 1 to 3.

For the purposes of NATCS, it was assumed that GPS receiver in OBU should track at least 5 satellites, for more accurate calculations and in the event of the loss of signal from one of them. Tests results showed that in the case of 99% of measurements at least 5 satellites were used for the purpose of location, The NATCS turned out to be flexible when it came to

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extending toll collection to every road category, every category of vehicle and, what's more, in terms of cost efficiency in implementation and operation. Another advantage is the absence of the need for new road infrastructure (gantries), while the operators can keep using the existing infrastructure. System works without toll booths, extra lanes, speed restrictions or complex structures along toll roads. Furthermore, the system was capable to support other value-added services on the same technology platform.

Test of NATCS project has been a complete success.

The system uses GPS/GSM technologies, as well as recognises devices such as DSRC and OBU. During tests, the system recognised four Tripon – EU OBU`s, French made DSRC Passango device and a German made Toll Collect device of the GPS/GSM type, installed in a vehicle which did not participate in the test, but accidentally ran through the control gate. This implied that the NATCS system is interoperable and can cooperate with both GPS/GSM systems as well as with DSRC types of systems existing in other EU Member States.

ACKNOWLEDGMENT

The paper has been prepared as a part of NATCS Pilot Project (N R10 0001 04) realised within the framework of the Applied Research Program of National Research Centre and Develpment.

REFERENCES

Černý, K., Electronic toll collection in the Czech Republic.

International Conference, Sofia (Bulgaria), 17.9.2008.

Commission Decision of 6 October 2009 on the definition of the European Electronic Toll Service and its technical elements. Official Journal of the European Union L 268/11, 13.10.2009.

Directive 2004/52/EC of the European Parliament and of the Council of 29 April 2004 on the interoperability of electronic road toll systems in the Community. OJ of the EU, L 166/132, 30.04.2004.

Kallweit, T., 2010. Technical Trial of ETC in Poland. Fela Management AG. Diessenhofen. 03/09/2010.

Kossak, A., 2009. Implemented and Envisaged Road Toll Policies in the Central-Eastern-European Countries.

Seminarium – PIARC TC A.3. Budapest, 6-7 May, 2009.

Standard EN ISO 12855. ETC. Information Exchange between Toll Provider and Toll Operator. 2010.

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Vehicle Engineering (VE) Volume 1 Issue 4, December 2013

Gabriel Nowacki

Awards:

Education:

Title: Leader ITS on the best Research Project in 2011.

Ewa Smoczyńska

High School of Radio Technology – Eng. 1976

Education:

University–UAM in Poznań–MSc. 1995

Warsaw School of Information Technology – Eng. 2009

National Defense University–Ph.D. 1999 Publications – 338 (total):10 monographs, 12 science research dissertations, 11 textbooks, 7 published series of lectures, 206 science papers (including 128 on international conferences), 92 reviews.

Scientific title: Professor of University Work: Military University of Technology/Cybernetics Faculty Awards:

Publications–6(total):1 monograph (DTP), 5 articles (including 2 on international conferences).

Work: Motor Transport Institute/Transport Telematics – Graphic.

Awards: Title: Leader ITS on the best Research Project in 2011.

Title: Leader ITS on the best Research Project in 2011.

Golden Order of Merit.

United Nations Medal – In the Sevice of Peace.

Anna Niedzicka Education: Polish-Japanese Institute of Information Technology Publications – 24 (total): 1 monograph (co-author), 21 articles (including 14 on international conferences).

Work: PUAV Quasar, Ambernet Sp. z o. o., Motor Transport Institute/Transport Telematics.

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The Project NATCS was granted title – Leader ITS in 2011 with category of the best Research Project on second edition Competition organized by ITS Poland, ITS Review with patronage of Infrastructure Ministry.