ISO/TS 16785:2020

TECHNICAL ISO/TS
SPECIFICATION 16785
Second edition
2020-03
Electronic Fee Collection (EFC) —
Application interface definition
between DSRC-OBE and external in-
vehicle devices
Perception du télépéage — Définition de l'interface entre
l'équipement à bord à communications dédiées à courte portée
(DSRC-OBE) et les dispostifs externes embarqués
Reference number
©
ISO 2020
© ISO 2020
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ii © ISO 2020 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols and abbreviated terms . 3
5 Tolling models with the in-vehicle device . 4
5.1 General . 4
5.2 Tolling model . 4
5.2.1 Operating environment . 4
5.2.2 Data exchanges . 6
6 Data group . 7
6.1 General . 7
6.2 Payment means status . 7
6.2.1 PaymentMode . 7
6.2.2 AccountStatus . 7
6.2.3 PaymentMeansBalance . 8
6.2.4 PaymentMeans . 8
6.2.5 PaymentMeansUnit . 8
6.2.6 PaymentSecurityData . 8
6.3 AccountUpdate . 8
6.3.1 General. 8
6.3.2 ReloadAccount . 8
6.3.3 SetAccount . . 9
6.3.4 AddToAccount . 9
6.4 PaymentFee . 9
6.4.1 PaymentFeeAmount . 9
6.4.2 Payment FeeUnit . 9
6.5 CCC attributes . 9
6.6 LAC data . 9
6.7 Other data . 9
7 Security aspects . 9
7.1 General . 9
7.2 OBE interface profile .10
Annex A (normative) Data type specification .11
Annex B (normative) Implementation conformance statement proforma .12
Annex C (informative) Clarification of data elements .16
Bibliography .20
Foreword
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iv © ISO 2020 – All rights reserved

Introduction
Background and motivation
In recent years, the road tolling policy in the world has spread to other than conventional toll road tolling
such as funding for road infrastructure management and maintenance, environmental measures, and
traffic management. Specifically, in order to accommodate the widespread use of low-fuel-consumption
and electric vehicles, introduction of road use tolling instead of fuel tax, congestion tolling on urban
roads and inter-urban roads is planned and implemented.
In the countries where dedicated short-range communication (DSRC)-based electronic fee collection
(EFC) systems are widely deployed, upgrading and extension of the schemes, to include presently non-
toll roads become a significant issue to be considered and solved.
This document describes how DSRC-based EFC systems, especially on-board equipment (OBE), can be
enhanced to meet these needs.
There are three cases of introducing EFC systems to cope with those situations:
— Case-1: Existing DSRC-based EFC system is extended and introduced on new roads.
— Case-2: Autonomous tolling system is introduced on both new roads and the existing toll roads.
— Case-3: DSRC-based EFC system continues to operate on existing toll roads, and the autonomous
tolling system is introduced on new toll roads.
For Case-1 and Case-2, the necessary interface definitions and the test procedures are already defined
by existing EFC standards. For Case-3 as shown in Figure 1, the OBE used for DSRC-based EFC can also
be used for the autonomous tolling system covering new roads and existing toll roads.
DSRC-OBE is possible to be reused for new EFC environments consisting of DSRC-based EFC and the
autonomous tolling system by expanding functionally by interfacing with the external in-vehicle device
that includes global navigation satellite systems (GNSS) module, cellular module and other related
modules.
Consequently, an application interface definition between DSRC-OBE and the external in-vehicle devices
is essential and needs to be standardized.
Figure 1 — Image of expanding toll roads and services (Case-3)
Purpose of this document
The purpose of this document is to provide support for enhanced functionalities of DSRC-OBE by means
of external in-vehicle devices.
This document aims at defining:
— A tolling model with the external in-vehicle devices (in the main part of the document);
— Definitions of data groups and data elements (in the main part of the document);
— Data type definition and implementation conformance statement (ICS) proforma (in Annexes A and B).
Applicable DSRC-OBE
There are five major DSRC standards currently deployed for EFC around the world. In standardizing
an application interface between DSRC-OBE and an external on-vehicle device, the interface should be
applied for every type of DSRC as shown in Figure 2.
Figure 2 — Applicable DSRC-OBE
Thanks to its operational reliability and robustness, DSRC-OBE is suitable for long-term use for EFC.
On the other hand, each component of external in-vehicle devices typically has a shorter product life
than DSRC-OBE in order to meet changing user demands for multi-functional and high performance
equipment.
Once an application interface has been standardized, DSRC-OBE can be used continuously in a variety
of EFC environments with an enhanced new external in-vehicle device as shown in Figure 3.
Figure 3 — Applicability for future upgrading
vi © ISO 2020 – All rights reserved

TECHNICAL SPECIFICATION ISO/TS 16785:2020(E)
Electronic Fee Collection (EFC) — Application interface
definition between DSRC-OBE and external in-vehicle
devices
1 Scope
This document defines an application interface between DSRC-based OBE (hereinafter referred to as
"DSRC-OBE") and an external in-vehicle device (hereinafter referred to as "the external device") to
make DSRC-OBE applicable for diversified external devices.
NOTE For use in autonomous tolling and DSRC-based (CEN, UNI, ARIB, TTA and GB/T) electronic fee
collection (EFC) systems. For use in urban and inter-urban toll schemes.
The scope of this document covers the following items (as shown in Figure 4):
— definitions of the application interface between DSRC-OBE and external devices, including global
navigation satellite system (GNSS), cellular network (CN) and controller area network (CAN) device;
— definitions of data groups and data elements.
Figure 4 — Scope of this document
The following items are out of the scope of this document:
— definitions of hardware components in the external device such as GNSS module, CN module and
mobile devices;
— definitions of the physical interface between DSRC-OBE and the external device such as USB and
Bluetooth;
— definition of ITS services other than EFC;
— definition of algorithms for authentication, encryption and key management.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC 8824-1, Information technology — Abstract Syntax Notation One (ASN.1): Specification of basic
notation — Part 1:
ISO/IEC 8825-2, Information technology — ASN.1 encoding rules: Specification of Packed Encoding Rules
(PER) — Part 2:
ISO 12813:2019, Electronic fee collection — Compliance check communication for autonomous systems
ISO 13141, Electronic fee collection — Localisation augmentation communication for autonomous systems
ISO 14906:2018, Electronic fee collection — Application interface definition for dedicated short-range
communication
ISO 17575-1:2016, Electronic fee collection — Application interface definition for autonomous systems —
Part 1: Charging
ISO 17575-3:2016, Electronic fee collection — Application interface definition for autonomous systems —
Part 3: Context data
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
attribute
addressable package of data consisting of a single data element or structured sequences of data
elements
3.2
autonomous tolling system
tolling system which is able to obtain usage data using on-board equipment independent from roadside
equipment
3.3
data element
coded information, which might itself consist of lower level information structures
3.4
data group
class of closely related attributes (3.1)
3.5
external in-vehicle device
component that can be connected to a piece of on-board equipment (OBE) in a vehicle
EXAMPLE Mobile phone or digital tachograph.
3.6
issuer
entity responsible for issuing the payment means to the user
3.7
on-board equipment
OBE
all required equipment on-board a vehicle for performing required electronic fee collection (EFC)
functions and communication services
2 © ISO 2020 – All rights reserved

3.8
on-board unit
OBU
single electronic unit on-board a vehicle for performing specific electronic fee collection (EFC) functions
and for communication with the external systems
3.9
roadside equipment
RSE
equipment located along the road, either fixed or mobile
3.10
toll service provider
TSP
entity providing toll services in one or more toll domains
3.11
transaction
whole of the exchange of information between two physically separated communication facilities
4 Symbols and abbreviated terms
For the purpose of this document, the following abbreviated terms apply throughout the document
unless otherwise specified.
ARIB Association of Radio Industries and Businesses
(Communication standardizing body in Japan)
ASN.1 Abstract Syntax Notation One (ISO/IEC 8824-1)
CAN Controller Area Network
CCC Compliance check Communication (ISO 12813)
CE Central Equipment
CN Cellular Network
DSRC Dedicated Short-Range Communication
EFC Electronic Fee Collection
GB/T Guojia Biaozhun/Tuijian (Chinese "Recommended National Standard")
GNSS Global Navigation Satellite System
HMI Human Machine Interface
ICC Integrated Circuit Card
ICS Implementation Conformance Statement
ITS Intelligent Transport Systems
LAC Localisation Augmentation Communication
OBE On-board Equipment
OBD On-board diagnostics
OBU On-board Unit
RSE Roadside Equipment
TSP Toll Service Provider
TTA Telecommunications Technology Association
(Communication standardizing body in Korea)
UNI Ente Nazionale Italiano di Unificazione
USB Universal Serial Bus
5 Tolling models with the in-vehicle device
5.1 General
The DSRC-OBE with an external device can support various EFC environments and further ITS services.
There are two kinds of settlement method in EFC, one is the on-board account system, and the other
method is the central account system. In the on-board account system, payment means may be
connected to DSRC-OBE as shown in Figure 5, and the toll amount determined by the tolling transaction
processes is directly deducted from payment means.
This document only address EFC schemes where the on-board account system is operated using an ICC.
Figure 5 — Arrangement of payment means
5.2 Tolling model
5.2.1 Operating environment
The system in which DSRC-OBE is connected to an external device should support the diversified tolling
system that supports both the autonomous tolling system and DSRC-based tolling system as shown in
Figure 6. In the diversified tolling system, the external device consists of the various components listed
in Table 1.
4 © ISO 2020 – All rights reserved

Table 1 — Configurations for tolling system
Tolling system DSRC-OBE Major components of the external device
GNSS CN device HMI Motion Interface
sensors
Digital CAN
tachograph (OBD-II)
DSRC tolling M — — — — — —
Diversified tolling M M M O O O O
M: Mandate, O: Option, —: not applicable
The external device included at minimum of GNSS receiver, cellular communication module and data
processing module. The following components are considered as optional parts for implementation
that depends on the requirements of the autonomous tolling system:
1) Motion sensors;
2) Digital tachograph interface;
3) Controller area network’s on-board diagnostics (CAN, OBD-II) interface.
The external device is connected with the toll service provider to exchange the reload-related data and
the autonomous tolling-related data defined by ISO 17575-1 through cellular networks. DSRC-OBE is
connected with individual RSE that exchange the related data for DSRC tolling, or compliance check or
localization using DSRC.
Whereas Figure 6 shows the configuration in which the external device and DSRC-OBE are physically
separated, it is also possible to integrate them into one unit in manufacturing a new OBE.
Figure 6 — Tolling model for the diversified tolling
5.2.2 Data exchanges
Figure 7 shows the general data exchanges between the external device and DSRC-OBE. Among these
are the data elements related to a vehicle that constitutes CCC att
...