ISO 13184-2:2016

Intelligent transport systems (ITS) — Guidance protocol via personal ITS station for advisory safety systems — Part 2: Road guidance protocol (RGP) requirements and specification

ISO 13184-2:2016 specifies the road guidance use cases on the DXM to provide the real-time decision support system to drivers or pedestrians using P-ITS-S. The road guidance protocol (RGP) is an instantiation of the data exchange message (DXM), which represents a generic message to exchange data between ITS stations. The RGP defines an interoperable service protocol between P-ITS-S and R-ITS-S for exchanging data elements. This part of ISO 13184 specifies the following: - Reference architecture for real-time decision support system. This reference architecture provides a general structure for the real-time decision support system and the method of message exchange between the P-ITS-S and the R-ITS-S. This reference architecture is used to build the interconnections between the P-ITS-S and the R-ITS-S. - Technique of application protocol design for various use cases on a P-ITS-S. This technique adopts a flexible and extendable protocol design. In many cases, the application protocol for the ITS is designed to provide a set of messages that is dependent on the use cases and the message exchange method. However, it is not easy to enumerate all use cases for some applications. The use cases can be changed or enhanced frequently. For this type of application, the protocol design, depending on the use cases, is not appropriate. This part of ISO 13184 provides a general technique of designing the road guidance application protocol based on the use cases. - Primitive data element. The primitive data element will be commonly used to configure the safety warning and parking guide service in the form of speed, location and time. - Use cases at the road and parking spaces for warning and parking guide. This part of ISO 13184 describes the use cases applicable to the communication services between the P-ITS-S and the R-ITS-S for the purposes of providing safety warning and parking guidance. ISO 13184 (all parts) have been aligned according to the requirements specified in ISO 21217, ISO/TS 17419 and ISO/TS 17423. ISO 13184-2:2016 only specifies the RGP messages based on the DXM definition (see Annex B and Annex C) at real-time. The content of the RGP messages are based on the definition of road guidance use cases as documented in ISO 13184?1. This part of ISO 13184 implements ITS-SU objects, which is a general reference to ITS application objects, ITS message sets and other objects which may require globally unique identification and registration. The management of ITS-SU objects is many-fold, e.g. specified in ISO 24102?4, ISO 24102?5, ISO 24102?6, ISO 24102?7, ISO 24102?8 and ISO 24102?9, and in CEN/ISO/TS 17423. This part of ISO 13184 implements authorized and controlled operation of ITS-SU objects, which requires considerations of ITS-SU object identifiers, i.e. ITS-AID, ITS-MsgSetID, ITS-SUID, ITS-SCUID, addresses and protocol identifiers used in the communication protocol stack of an ITS-S, and others. NOTE The accuracy of the navigation and positioning system as input to the Road Guidance application is important for road guidance but is not part of the ISO 13184 series. Detailed information about crossroads is needed for implementation of Road Guidance applications.

Systèmes intelligents de transport — Protocole d'orientation par station ITS personnelle pour systèmes à avis de sécurité — Partie 2: Spécifications et exigences du protocole d'orientation routière

General Information

• Status: Published
• Publication Date: 18-May-2016
• ICS: 03.220.01 - Transport in general
• ICS: 35.240.60 - IT applications in transport
• Technical Committee: ISO/TC 204 - Intelligent transport systems
• Drafting Committee: ISO/TC 204/WG 17 - Nomadic Devices in ITS Systems
• Current Stage: 9060 - Close of review
• Completion Date: 02-Dec-2026

Relations

• Consolidated By: ISO/TS 17574:2017 - Electronic fee collection — Guidelines for security protection profiles
• Effective Date: 06-Jun-2022

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 13184-2
First edition
2016-05-15
Intelligent transport systems (ITS) —
Guidance protocol via personal ITS
station for advisory safety systems —
Part 2:
Road guidance protocol (RGP)
requirements and specification
Systèmes intelligents de transport — Protocole d’orientation par
station ITS personnelle pour systèmes à avis de sécurité —
Partie 2: Spécifications et exigences du protocole d’orientation
routière
Reference number
©
ISO 2016
© ISO 2016, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
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ii © ISO 2016 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 2
3 Terms and definitions . 2
4 Abbreviated terms . 3
5 Conventions . 4
6 Road guidance implementation overview . 4
7 Use cases implementation into the road guidance protocol . 7
7.1 Use case clusters overview . 7
7.2 Use cases implementation . 9
7.2.1 UC cluster 1 — Crossroads with a traffic signal . 9
7.2.2 UC cluster 2 — Crossroads .13
7.2.3 UC cluster 3 — Parking space .14
7.2.4 UC cluster 4 — Risky environment alarm .15
8 RGP messages .21
8.1 Overview .21
8.2 Real-time RGP “Data eXchange Message” communication .22
9 RGP defined data exchange messages .24
9.1 General Data eXchange Message definition .24
9.2 notify-on-position.25
9.2.1 Definition .25
9.2.2 Example .28
9.3 stop-notify .29
9.3.1 Definition .29
9.3.2 Example .29
9.4 collision-possible .30
9.4.1 Definition .30
9.4.2 Example .32
9.5 vehicle-blocks-road .32
9.5.1 Definition .32
9.5.2 Example .33
9.6 pedestrian-blocks-road .34
9.6.1 Definition .34
9.6.2 Example .34
9.7 bumper-to-bumper .35
9.7.1 Definition .35
9.7.2 Example .35
9.8 crossing-priority .36
9.8.1 Definition .36
9.8.2 Example .36
9.9 oncoming-vehicle .37
9.9.1 Definition .37
9.9.2 Example .37
9.10 overspeed .38
9.10.1 Definition .38
9.10.2 Example .39
9.11 bad-weather .39
9.11.1 Definition .39
9.11.2 Example .41
9.12 speed-limit .42
9.12.1 Definition .42
9.12.2 Example .42
9.13 road-occupation .43
9.13.1 Definition .43
9.13.2 Example .44
9.14 emergency-vehicle .45
9.14.1 Definition .45
9.14.2 Example .46
9.15 release.47
9.15.1 Definition .47
9.15.2 Example .47
9.16 search-parking-space .48
9.16.1 Definition .48
9.16.2 Example .50
9.17 guide-parking-space .51
9.17.1 Definition .51
9.17.2 Example .52
Annex A (normative) Vehicle Interface Data Format (VIDF) .54
Annex B (normative) Data eXchange Message definition .74
Annex C (normative) Data eXchange Message ASN.1 definition .76
Annex D (informative) Requirements .82
Bibliography .83
iv © ISO 2016 – All rights reserved

Foreword
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bodies (ISO member bodies). The work of preparing International Standards is normally carried out
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electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
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For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical
Barriers to Trade (TBT), see the following URL: Foreword — Supplementary information.
The committee responsible for this document is ISO/TC 204, Intelligent transport systems.
ISO 13184 consists of the following parts, under the general title Intelligent transport systems (ITS) —
Guidance protocol via personal ITS station for advisory safety systems:
— Part 1: General information and use cases definition
— Part 2: Road guidance protocol (RGP) requirements and specification
Additional part dealing with road guidance protocol (RGP) conformance test specification is under
preparation.
Introduction
This part of ISO 13184 specifies the use cases implementation of a real-time decision support system for
guidance information, designed to enhance mobility and vehicle safety and to provide a parking guide
service using the Personal ITS Station (P-ITS-S). The purpose of the system is to transmit guidance or
warning messages to drivers and pedestrians in real-time, enhance the user’s convenience and avoid
congestion in parking facilities by preventing accidents and enabling easy parking.
This part of ISO 13184 implements the road guidance protocol (RGP) requirements (derived from the
use cases defined in ISO 13184–1) based on the Data eXchange Message (DXM) at the application level
regarding the safety warning and parking guide services between the Roadside ITS Station (R-ITS-S)
installed at the roadside and the user’s Personal ITS Station (P-ITS-S), e.g. Nomadic Device.
This part of ISO 13184 covers subjects related to traffic safety, including pedestrians besides vehicle
drivers. Therefore, this DXM implementation describes how the safety-related services are provided
using the P-ITS-S.
This system is based on the following assumptions.
— Based on the fact that the P-ITS-S has limited resources considers these limitations.
— Use cases related to the safety warning and parking guide service can be classified in various ways.
These use cases can be added or deleted frequently depending on the specific circumstances of
roads and parking spaces. Therefore, the DXM implementation design needs to be flexible and
extendable, which enables to add or delete the use cases conveniently.
— The DXM implementation of road guidance contains data elements to configure the message
transmitted between the ITS Stations.
— The major use cases include safety warnings at roads and parking guide services to be used between
the R-ITS-S and the P-ITS-S.
vi © ISO 2016 – All rights reserved

INTERNATIONAL STANDARD ISO 13184-2:2016(E)
Intelligent transport systems (ITS) — Guidance protocol
via personal ITS station for advisory safety systems —
Part 2:
Road guidance protocol (RGP) requirements and
specification
Systèmes intelligents de transport -- Protocole d’orientation par station ITS personnelle pour systèmes à
avis de sécurité -- Partie 2
1 Scope
This part of ISO 13184 specifies the road guidance use cases on the DXM to provide the real-time
decision support system to drivers or pedestrians using P-ITS-S. The road guidance protocol (RGP) is
an instantiation of the data exchange message (DXM), which represents a generic message to exchange
data between ITS stations.
The RGP defines an interoperable service protocol between P-ITS-S and R-ITS-S for exchanging data
elements. This part of ISO 13184 specifies the following:
— Reference architecture for real-time decision support system.
This reference architecture provides a general structure for the real-time decision support
system and the method of message exchange between the P-ITS-S and the R-ITS-S. This reference
architecture is used to build the interconnections between the P-ITS-S and the R-ITS-S.
— Technique of application protocol design for various use cases on a P-ITS-S.
This technique adopts a flexible and extendable protocol design. In many cases, the application
protocol for the ITS is designed to provide a set of messages that is dependent on the use cases
and the message exchange method. However, it is not easy to enumerate all use cases for some
applications. The use cases can be changed or enhanced frequently. For this type of application, the
protocol design, depending on the use cases, is not appropriate. This part of ISO 13184 provides a
general technique of designing the road guidance application protocol based on the use cases.
— Primitive data element.
The primitive data element will be commonly used to configure the safety warning and parking
guide service in the form of speed, location and time.
— Use cases at the road and parking spaces for warning and parking guide.
This part of ISO 13184 describes the use cases applicable to the communication services between
the P-ITS-S and the R-ITS-S for the purposes of providing safety warning and parking guidance.
ISO 13184 (all parts) have been aligned according to the requirements specified in ISO 21217,
ISO/TS 17419 and ISO/TS 17423.
This part of ISO 13184 only specifies the RGP messages based on the DXM definition (see Annex B
and Annex C) at real-time. The content of the RGP messages are based on the definition of road guidance
use cases as documented in ISO 13184–1.
This part of ISO 13184 implements ITS-SU objects, which is a general reference to ITS application
objects, ITS message sets and other objects which may require globally unique identification and
registration.
The management of ITS-SU objects is many-fold, e.g. specified in ISO 24102–4, ISO 24102–5, ISO 24102–
6, ISO 24102–7, ISO 24102–8 and ISO 24102–9, and in CEN/ISO/TS 17423. This part of ISO 13184
implements authorized and controlled operation of ITS-SU objects, which requires considerations of
ITS-SU object identifiers, i.e. ITS-AID, ITS-MsgSetID, ITS-SUID, ITS-SCUID, addresses and protocol
identifiers used in the communication protocol stack of an ITS-S, and others.
NOTE The accuracy of the navigation and positioning system as input to the Road Guidance application is
important for road guidance but is not part of the ISO 13184 series. Detailed information about crossroads is
needed for implementation of Road Guidance applications.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO/TS 17419, Intelligent transport systems — Cooperative systems — Classification and management of
ITS applications in a global context
ISO/TS 17423, Intelligent transport systems — Cooperative systems — ITS application requirements and
objectives for selection of communication profiles
ISO 21217, Intelligent transport systems — Communications access for land mobiles (CALM) — Architecture
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/TS 17419, ISO/TS 17423,
ISO 21217 and the following apply.
3.1
FA-SAP
service access point between facilities and application layer
3.2
GPS coordinates
collection of GPS position and time
3.3
GPS position
collection of GPS latitude, longitude and altitude
3.4
ITS-S capability (ITS-S capabilities)
uniquely addressable protocol functionality
3.5
ITS station
ITS-S
entity in a communication network, comprised of application, facilities, networking and access layer
components specified in ISO 21217 that operate within a bounded secure management domain
3.6
ITS-S application process
ITS-S AP
element in an ITS station that performs information processing for a particular application, and uses
ITS-S services to transmit and receive information
2 © ISO 2016 – All rights reserved

3.7
ITS-S application process provisioner
ITS-S APP
functionality in an ITS-SU offering ITS-S application processes (3.6) for download and installation to
other ITS-Ss
3.8
personal ITS station
P-ITS-S
implementation of an ITS station as personal ITS subsystem
Note 1 to entry: P-ITS-S is used to send the information of each user (drivers and pedestrians) to the roadside ITS
station, and receives the safety warning and parking guide service and transfers them to the users.
3.9
roadside ITS station
R-ITS-S
system that receives and processes vehicular and pedestrian information within a certain zone and
determines the situation, in order to provide the safety warning and parking guide service to vehicles
and pedestrians
Note 1 to entry: The system is installed at the roadside.
3.10
sensor
device designed to collect general information (e.g., road surface state, potential hazard vehicle’s speed)
within the server’s zone
3.11
WGS-84 coordinate system
WGS-84 is the reference system used in the satellite-based positioning system NAVSTAR Global
Positioning System (GPS)
Note 1 to entry: The World Geodetic System (WGS) is a standard for use in cartography, geodesy, and navigation.
The latest revision is WGS-84.
4 Abbreviated terms
ADU application data unit
AP application process
ASN.1 abstract syntax notation one
BT Bluetooth
C conditional
C-ITS-S central–intelligent transport system–station
CRC cyclic redundancy check
Cvt convention (M, O, C)
DER distinguished encoding rules
DTC diagnostic trouble code
DXM data exchange message
FA-SAP facility application–service access point
GPS global positioning system
HTML hypertext mark-up language
ITS intelligent transport systems
ITS-AID intelligent transport systems–application identifier
ITS-MsgSetID intelligent transport systems–message set identifier
ITS-S intelligent transport systems–station
ITS-SU intelligent transport systems–station unit
ITS-SCUID intelligent transport systems–station communication unit identifier
ITS-SUID intelligent transport systems–station unit identifier
ITS-S AP intelligent transport systems–ITS-S application process
ITS-S APP intelligent transport systems–ITS-S application process provisioner
L2CAP logical link control and adaptation protocol
M mandatory
ND nomadic device
O optional
OBEX object exchange
OSI open systems interconnection
PER packed encoding rules
P-ITS-S personal–intelligent transport system-station
R-ITS-S roadside–intelligent transport system-station
RGP road guidance protocol
SDP service discovery protocol
SGML standard generalized mark-up language
UCDF use case description format
UGP unified gateway protocol
VIN vehicle identification number
V-ITS-SG vehicle–intelligent transport system-station gateway
WGS-84 World Geodetic System 1984
5 Conventions
This part of ISO 13184 is based on the conventions discussed in the OSI Service Conventions
(ISO/IEC 10731) as they apply for communication services. The vehicle data transfer protocol is
applicable to OSI layers 5, 6 and 7.
6 Road guidance implementation overview
The Road Guidance will be implemented in Data eXchange Message (DXM) which is another way of
transmitting data. Other standards directly define ASN.1 elements for every parameter (see ETSI
EN 302 637–2, SAE J2735 or ETSI/TS 101 539–1). However, DXM defines data parameters, its types,
units, etc. DXM defines flexible messages because every message consists of a message ID (iTSmsID)
and a list of registered value identifiers (rvIds) referencing data parameters. New messages can be
defined by adding rvIds to the list, new data parameters can be defined by referring data types.
The road guidance DXM implementation considers conditions such as limited resources because
the user receives the service from a P-ITS-S. It is undesirable that all use cases be implemented and
installed in a light-weight nomadic device, as elements of the road environment, such as crossroads
and the parking environment, are very diverse in their forms. In addition, the service environment at
crossroads and parking spaces varies, depending on the time and the area, and undergoes a relatively
large number of changes. Therefore, use cases may need to be added/modified/deleted. As a result,
the nomadic device can work as an obstacle to smooth service provisioning and service expansion, as
it has the burden of updating the use cases manually according to its necessity. This part of ISO 13184
proposes a light-weight P-ITS-S that can resolve these challenges.
The DXM handler allows sending of information between two ITS stations [i.e. a personal ITS station
sends its user type (pedestrian, vehicle, etc.) and GPS position to a roadside ITS station; a roadside ITS
station sends a collision possible message, including its position to the personal ITS station]. The DXM
4 © ISO 2016 – All rights reserved

handler is an ITS-S facilities layer ITS-S capability and an ITS-S application process (see Figure 1). The
relation between the APPs on a personal ITS station or the application on a roadside ITS station and
a DXM handler is realized through FA-SAP (API). FA-SAP primitives defined in ISO/TS 17429 can be
used for this purpose. APPs request the use of the DXM ITS-S capability at time of flow registration.
DXM ITS-S capability formats the packets based on RGP defined use cases. As per conformance with
ISO/TS 17419 and ISO/TS 17423, add in the overview the process by which a road guidance application
(ITS-S application process) gets installed in an ITS station and registered with the ITS station
management entity, together with its communication requirements, defined for each type of messages
exchanged between the Personal ITS-S, Roadside ITS-S and Central ITS-S should be prepared by ITS-S
application process(s) (ITS-S AP).
Figure 1 — Communication flow
Figure 2 shows the communication of the road guidance implementation using the DXMessage, i.e. the
P-ITS-S starts with “App” handling only messages from and to the R-ITS-Ss. The P-ITS-S is pre-loaded
with the DXM configuration using case(s)-specific configuration information from the C-ITS-S (1) to
support road guidance messages and data parameters.
After a road user (vehicle, pedestrian) enters a road guidance zone of an R-ITS-S (3), the P-ITS-S
immediately reports its position and motion parameters with the necessary message to the R-ITS-S (4).
If a situation occurs in the road guidance zone, which matches a supported use case, the R-ITS-S notifies
the situation (i.e. safety warning, parking guidance) information to the P-ITS-S (5). The P-ITS-S shows
the situation on the display and/or does some acoustic signals. On leaving the road guidance zone, the
P-ITS-S stops the communication to the R-ITS-S (6).
Key
0 update configuration by download
1 road guidance zone
2 sending position and motion information to R-ITS-S
3 sending problem notification
4 sending stop notification/leaving road guidance zone
Figure 2 — Road guidance protocol message exchange scenario
Independent from the P-ITS-S to C-ITS-S/R-ITS-S communication, new messages and their parameters
have to be communicated from the C-ITS-Ss to all R-ITS-Ss. In addition, the applications have to be
modified and provided in the App Store to support all use cases.
The use case implementation of the RGP is defined in Clause 7.
On the P-ITS-S, a Road Guidance Client ITS-S application process uses the DXM Handler ITS-S capability
to communicate to R-ITS-Ss. It uses a broadcast to send its road user type, GPS coordinates and
additional data to inform surrounding R-ITS-Ss that it is interested in messages concerning its position
(see Figure 3). So the P-ITS-S is added to the list of interested stations of the R-ITS-S.
If an R-ITS-S recognized problems in its communication area, it sends DXM containing the problem
information to all list members of interested stations.
6 © ISO 2016 – All rights reserved

Key
1 P-ITS-S sends a broadcast — to inform all possible R-ITS-Ss: “I am interested”
2 R-ITS-Ss send possible problems to all interested stations
Figure 3 — Communication between P-ITS-Ss and R-ITS-Ss
Every RGP message is encoded as DXM. The DXM will be transmitted with an Application Data Unit
(ADU) by the road guidance Application Process (AP) using the ITS-S layer facilities.
7 Use cases implementation into the road guidance protocol
7.1 Use case clusters overview
Table 1 provides an overview of the different use cases. The use cases are grouped into use case clusters.
Table 1 — Overview of use case clusters and associated use cases
# Title of use
Brief description
case cluster
1  Crossroads This cluster is separated into five use cases by taking the signal violating vehicle as a risk
with a traffic factor. A vehicle at a crossroad is controlled by the signalling system of the traffic signal. The
signal use cases presented in this cluster are designed to provide a service for smooth crossroad
traffic control while complying with the signalling system and protecting pedestrians on a
pedestrian crossing.
UC 1.1 — Vehicle violates a signal without stopping
UC 1.2 — Violating vehicle is inside the crossroad
UC 1.3 — Guiding the pedestrian on a pedestrian crossing
UC 1.4 — Pedestrians violate the traffic signal on a pedestrian crossing
UC 1.5 — The traffic is bumper-to-bumper on the crossroad
2  Crossroads This use case considers the scenario that the crossroad is not equipped with a traffic signal,
which may cause the traffic congestion if several vehicles enter into the crossroad simulta-
neously. This use case is designed to provide smooth traffic flow by preventing heavy traffic
congestion or reducing waiting time.
UC 2.1 — Crossroads without a traffic signal
3  Parking space This cluster describes two use cases for the parking guide.
UC 3.1 — Parking guide when the vehicle enters a parking area
UC 3.2 — Searching the path and parking space on demand
The parking path guide in the parking space use case refers to simple transmission of the
path to the user’s personal ITS station, not to the vehicle navigation system.
When a vehicle enters into the parking space, it is difficult for the vehicle driver to check how
many parking lots are available at which space. Therefore, if the parking space is full or if a
parking space is available but cannot be identified conveniently, the driver will waste time to
park the vehicle or even unable to find a parking space for the vehicle. In addition, the driver
may not be able to park the vehicle at the convenient space.
4  Risky envi- This cluster describes two use cases that consider the frequent accidents area at the
ronment alarm curved road.
UC 4.1 — Vehicle strays into the path of an oncoming vehicle
UC 4.2 — Vehicle approaches the curved road with excessive speed
The cluster considers the oncoming vehicle and speed limit regulation. The use cases focus
on reducing and preventing the accident which can be caused by the geometric structure of
the road.
The following two use cases consider the speed limit of the vehicles with some special cases
that contain school zone and severe weather condition.
UC 4.3 — Risky environments alarm in severe weather condition
UC 4.4 — Risky environments alarm in the areas of speed limit enforcement
The use cases help safe driving by informing of the presence of the school zone and the se-
vere weather condition.
8 © ISO 2016 – All rights reserved

Table 1 (continued)
# Title of use
Brief description
case cluster
The following two use cases consider temporary road occupation scenarios and the situation
of an emergency vehicle to establish a clear path.
UC 4.5 — Vehicle approaches a temporary road occupation
This use case addresses the situation when a vehicle approaches a temporary road occupa-
tion such as the road construction, accident/disabled vehicles or obstacles on the road. By
informing the status of temporary road occupation, the road congestion will be prevented.
UC 4.6 — Emergency vehicle approaches on one’s route
This use case addresses the situation when an emergency vehicle is moving to establish a
clear path. This cluster handles the safety messaging procedure when an emergency vehicle
is approaching. By announcing the emergency vehicle approaching information, an emergen-
cy vehicle can achieve a clear path.
7.2 Use cases implementation
7.2.1 UC cluster 1 — Crossroads with a traffic signal
7.2.1.1 UC 1.1 — Vehicle violates a signal without stopping
Table 2 defines the use case handling when a vehicle violates a stop signal at the crossroads.
Table 2 — Definition of UC 1.1 — Vehicle violates a signal without stopping
Cluster 1 — Crossroads with a When a vehicle enters a crossroad and cannot

traffic signal stop on the stop line due to the long braking
distance and velocity of the vehicle, the warning
Name UC 1.1 — Vehicle violates
message is sent to all vehicles and pedestrians. If
a signal without stopping
the vehicle is able to stop on the line, the warn-
ing message may disappear.
Occurrence Crossroads with a traffic signal.

area
Road user Accessing the crossroads.

situation
Provisioning a)  The vehicle accesses the crossroads.
phase
b)  Forecasts that the vehicle can violate the signal when entering into the
crossroads.
Use Case
c)  Sends the information message with handling of risk factors as soon as any
vehicle poses a risk.
d)  Sends the release message when the vehicle arrives at the stop line.
P-ITS-S The following references are related to “Provisioning phase”:
control
to c)  Caution/Warning message.
to d)  Release message.
Hindrance Signals of the traffic signal should be known in advance to forecast the signal.

factor
Requirements When the user receives the information message, the user must pay atten-

tion to it.
Reference Signal violation forecasting of this system is closely related to the driver’s
response time and braking distance. Therefore, environmental circumstances

such as the vehicle type and the state of the road surface may be considered as
the major factors to apply this service.
Clause Name Exe Description
Table 2 (continued)
notify-on-po-
9.2 P/V Send P-ITS-S position, motion parameter and
sition
vehicle size to the road side server (R-ITS-S) on
entering R-ITS-Ss communication area. After the
first contact, send only the P-ITS-S position in a
predefined time interval.
stop-notify
Messages 9.3 P/V Stop the communication to the R-ITS-S.
colli-
9.4 R Send notification message to indicate a vehicle
sion-possible
possibly violating a crossing signal, including

crossing position and blocked lanes. Send updated
message if blocked lanes have changed its status.
release
9.15 R Release message if problem no longer occurs.
7.2.1.2 UC 1.2 — Violating vehicle is inside the crossroad
Table 3 defines the use case handling procedure when a vehicle violates the stop signal and locates
inside the crossroad. This situation is similar to the use case shown in 7.2.1.1. However, unlike 7.2.1.1,
this use case considers the handling procedure when a vehicle has already violated the traffic signal.
Table 3 — Definition of UC 1.2 — Violating vehicle is inside the crossroad
Cluster 1 — Crossroads with a If a vehicle crosses over the stop line and enters

traffic signal inside the crossroad, or the vehicle has violated
the stop line and keeps moving even with the
Name UC 1.2 — Violating vehicle
stop signal, the warning message is sent to the
is inside the crossroad
surrounding vehicles. The warning message is

also sent to pedestrians who have received a
clear signal at the pedestrian crossing.
Occurrence Crossroads with a traffic signal.

area
Road user The clear signal is on.

situation
Provisioning a)  Checks whether a vehicle violates the signal at the crossroad when the traf-
phase fic signal has changed.
b)  Generates a caution message that the vehicle violating the traffic signal has
been detected. As soon as the signal has changed, the vehicle in violation of the
Use Case
signal is identified and the caution message is sent to the surrounding vehicles
and pedestrian which receives the clear signal.
c)  Generates a release message if the vehicle that has violated the traffic signal
exits the crossroad.
P-ITS-S The following references are related to “Provisioning phase”:
control
to c)  Caution/Warning message.
to d)  Release message.
Hindrance Vehicle making a right turn.

factor
Requirements Pay attention to the warning message.
Reference The vehicle attempts to make a right turn and the vehicle in violation of the

traffic signal cannot be clearly identified.
Clause Name Exe Description
notify-on-posi-
9.2 P/V Send P-ITS-S position, motion parameter and
tion
vehicle size to the road side server (R-ITS-S) on
entering R-ITS-Ss communication area. After
the first contact, send only the P-ITS-S position
in a predefined time interval.
10 © ISO 2016 – All rights reserved

Table 3 (continued)
stop-notify
Messages 9.3 P/V Stop the communication to the R-ITS-S.
vehi-
9.5 R Send notification message to indicate a vehicle
cle-blocks-road
blocks a crossing road, including crossing posi-

tion and blocked lanes. Send updated message if
blocked lanes have been changed.
release
9.15 R Release message if problem no longer occurs.
7.2.1.3 UC 1.3 — Guiding the pedestrian on a pedestrian crossing
Table 4 defines the use case handling procedure if the remaining time of clear signal is short when the
pedestrians cross the pedestrian crossing.
Table 4 — Definition of UC 1.3 — Guiding the pedestrian on a pedestrian crossing
Cluster 1 — Crossroads with a If a pedestrian accesses the pedestrian cross-

traffic signal ing, the remaining time of the clear signal is
compared with the average walking time, and
Name UC 1.3 — Guiding the
the guide message is sent. In addition, if the sig-
pedestrian on a pedestrian
nalling time at a pedestrian crossing is short, the

crossing
remaining time of clear signal is notified to the
pedestrian at the pedestrian crossing.
Occurrence Crosswalks with a traffic signal.

area
Road user Remaining clear signal time needed.

situation
Provisioning a)  Checks the remaining time of clear signal.
phase
b)  Checks the average walking time.
c)  Generates a guide message that the remaining time of clear signal is notified
Use Case
to the pedestrian. The remaining time of the clear signal is compared with the
average walking time, and the guide message is sent. In addition, if the signalling
time at a pedestrian crossing is short, the remaining time of clear signal is noti-
fied to the pedestrian at the pedestrian crossing.
P-ITS
...