SIST EN ISO 18750:2018

SLOVENSKI STANDARD
01-september-2018
1DGRPHãþD
SIST-TS CEN ISO/TS 18750:2015
,QWHOLJHQWQLWUDQVSRUWQLVLVWHPL.RRSHUDWLYQLVLVWHP/RNDOQLGLQDPLþQL
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Intelligent transport systems - Cooperative ITS - Local dynamic maps (ISO 18750:2018)
Intelligente Transportsysteme - Kooperative Systeme - Festlegung eines globalen
Konzeptes für lokale dynamische Karten (ISO 18750:2018)
Systèmes intelligents de transport - Systèmes ITS - Cartes dynamiques locales (ISO
18750:2018)
Ta slovenski standard je istoveten z: EN ISO 18750:2018
ICS:
03.220.20 Cestni transport Road transport
35.240.60 Uporabniške rešitve IT v IT applications in transport
prometu
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 18750
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2018
EUROPÄISCHE NORM
ICS 03.220.20; 35.240.60 Supersedes CEN ISO/TS 18750:2015
English Version
Intelligent transport systems - Co-operative ITS - Local
dynamic map (ISO 18750:2018)
Systèmes de transport intelligents - Systèmes Intelligente Transportsysteme - Kooperative Systeme -
intelligents de transport coopératifs - État des Festlegung eines globalen Konzeptes für lokale
connaissances des cartes (ISO 18750:2018) dynamische Karten (ISO 18750:2018)
This European Standard was approved by CEN on 12 June 2018.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 18750:2018 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 18750:2018) has been prepared by Technical Committee ISO/TC 204
"Intelligent transport systems" in collaboration with Technical Committee CEN/TC 278 “Intelligent
transport systems” the secretariat of which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by December 2018, and conflicting national standards
shall be withdrawn at the latest by December 2018.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes CEN ISO/TS 18750:2015.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 18750:2018 has been approved by CEN as EN ISO 18750:2018 without any modification.

INTERNATIONAL ISO
STANDARD 18750
First edition
2018-05
Intelligent transport systems —
Co-operative ITS — Local dynamic
map
Systèmes de transport intelligents — Systèmes intelligents de
transport coopératifs — État des connaissances des cartes
Reference number
ISO 18750:2018(E)
©
ISO 2018
ISO 18750:2018(E)
© ISO 2018
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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.
ISO copyright office
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Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved

ISO 18750:2018(E)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols and abbreviated terms . 3
5 Architectural environment . 4
5.1 Local Dynamic Map . 4
5.2 LDM in an ITS-S . 4
5.3 LDM in an ITS-SU . 5
5.4 LDM related processes . 7
5.4.1 Synchronization of LDMs . 7
5.4.2 Archiving of LDM Data Objects . 7
5.5 LDM for road safety and vehicle-to-vehicle applications . 7
5.6 Security perspective . 8
5.6.1 Authorised access to LDM . 8
5.6.2 Initialisation and installation of applications to the BSMD . 8
5.6.3 Privacy . 9
5.7 An LDM versus other similar functionalities in an ITS-SU . 9
6 Functionality . 9
6.1 Terms and conventions . 9
6.2 Structure of an LDM .11
6.3 LDM Data Storage .12
6.4 LDM services .14
6.4.1 Registration, deregistration, and revocation of ITS-S application processes .14
6.4.2 Security checking in access requests .14
6.4.3 Access request management .15
6.5 LDM maintenance . .17
6.5.1 LDM Area of Maintenance .17
6.5.2 Outdated data management .17
6.6 LDM knowledge base .17
6.6.1 Metadata .17
6.6.2 Utility functions .18
6.7 Interfaces .18
6.7.1 Types of interfaces .18
6.7.2 Parameters of interface functions .19
6.7.3 LDM application management interface .20
6.7.4 LDM data interface .22
6.7.5 Security interface .25
6.7.6 LDM management interface .26
6.7.7 Service access points .27
7 Procedures .30
7.1 LDM services .30
7.1.1 Registration, deregistration, and revocation of ITS-S application processes .30
7.1.2 Security checking in access requests .30
7.1.3 Access request management .30
7.1.4 Second level filtering .32
7.2 LDM maintenance . .33
7.2.1 Area management .33
7.2.2 Outdated data removal .33
7.3 LDM knowledge data base .33
7.4 Interfaces .33
ISO 18750:2018(E)
7.5 LDM management .33
7.5.1 Registration of LDM at ITS-S management entity .33
7.5.2 Multiple ITS-SCUs .33
Annex A (normative) ASN.1 modules .35
Annex B (normative) LDM Data Dictionary .48
Annex C (informative) Examples of LDM-DOs .50
Annex D (informative) Location-Referencing .57
Annex E (informative) Time-Referencing .61
Annex F (normative) Implementation Conformance Statement proforma .62
Bibliography .68
iv © ISO 2018 – All rights reserved

ISO 18750:2018(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
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
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www .iso .org/iso/foreword .html.
This document was prepared by ISO/TC 204, Intelligent transport systems.
This first edition cancels and replaces the first edition (ISO/TS 18750:2015), which has been technically
revised.
ISO 18750:2018(E)
Introduction
[17]
An essential property of cooperative intelligent transport systems (C-ITS), see ISO TR 17465-1 , is
the sharing of data between different ITS applications providing different ITS services to the users.
This approach replaces the traditional approach where each application is operated in an isolated
environment, i.e. referred to as "silo - approach". The C-ITS approach enables synergies in components
of an ITS station unit, e.g. sharing of communication tools, improves overall performance and reliability,
and reduces overall cost. In order to protect the interests of the various ITS applications, C-ITS
implements the concept of an ITS station operated as a bounded secured managed domain.
The sharing of data between applications is achieved by subscribe/publish mechanisms, where at
least two mechanisms are distinguished, i.e. one allowing ITS-S application processes to subscribe to
standardized messages from ITS message sets (direct forwarding upon reception of such messages
in an ITS station unit), and one using a local dynamic map (LDM) as repository of standardized data
objects. Such data objects stored in an LDM are named LDM Data Objects (LDM-DOs). LDM-DOs provide
self-consistent information on real objects existing at a given geo-location during a given lifetime-
interval. Authorized ITS-S application processes may add LDM-DOs to an LDM, and may retrieve LDM-
DOs from an LDM. Retrieval of LDM-DOs may be performed in queries and by means of subscription. A
subscription will result in automatic notifications of selected LDM Data Objects either in defined time
intervals, or event driven.
This document introduces the usage of LDMs, and specifies the LDM for global usage in C-ITS.
[40] [42]
Initial implementations of LDMs were in the EU research projects CVIS and Safespot .
vi © ISO 2018 – All rights reserved

INTERNATIONAL STANDARD ISO 18750:2018(E)
Intelligent transport systems — Co-operative ITS — Local
dynamic map
1 Scope
This document:
— describes the functionality of a "Local Dynamic Map" (LDM) in the context of the "Bounded Secured
Managed Domain" (BSMD);
— specifies:
— general characteristics of LDM Data Objects (LDM-DOs) that may be stored in an LDM, i.e.
information on real objects such as vehicles, road works sections, slow traffic sections, special
weather condition sections, etc. which are as a minimum requirement location-referenced and
time-referenced;
— service access point functions providing interfaces in an ITS station (ITS-S) to access an LDM for:
— secure add, update and delete access for ITS-S application processes;
— secure read access (query) for ITS-S application processes;
— secure notifications (upon subscription) to ITS-S application processes;
— management access:
— secure registration, de-registration and revocation of ITS-S application processes at
LDM;
— secure subscription and cancellation of subscriptions of ITS-S application processes;
— procedures in an LDM considering:
— means to maintain the content and integrity of the data store;
— mechanisms supporting several LDMs in a single ITS station unit.
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
ISO/IEC 8825-2, Information technology — ASN.1 encoding rules: Specification of Packed Encoding Rules
(PER) — Part 2
ISO/IEC 9646-7, Information technology — Open Systems Interconnection — Conformance testing
methodology and framework — Part 7: Implementation Conformance Statements
ISO 21217, Intelligent transport systems — Communications access for land mobiles (CALM) — Architecture
ISO 18750:2018(E)
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:
— IEC Electropedia: available at http: //www .electropedia .org/
— ISO Online browsing platform: available at https: //www .iso .org/obp
3.1
data integrity
property that data has not altered or destroyed in an unauthorized manner
[SOURCE: ISO 24534-5]
3.2
International Atomic Time
time since 00:00:00 UTC, 1 January, 2004, identical with UTC except that no leap seconds need to be added
3.3
LDM Area of Interest
location requirement used in the filter process of queries and automatic notifications
3.4
LDM Area of Maintenance
information on the operational location area of an LDM used by LDM maintenance
[30]
Note 1 to entry: ETSI EN 302 895 restricts the LDM Area of Maintenance to "geographical area specified by
the LDM for LDM maintenance".
3.5
LDM Permissions
information on how a specific ITS-S application process may use an LDM
3.6
LDM Data Object
location-referenced and time-referenced representation of a real object that is self-explanatory without
any further context information
3.7
LDM Data Object ID
identifier of an LDM Data Object which is unique in an LDM
3.8
LDM Data Dictionary
dictionary of LDM Data Object Types
3.9
LDM Data Object Type
identifier of the type of information contained in an LDM Data Record
3.10
Location Validity
information indicating a location at which an LDM Data Object is valid
3.11
Time Validity
information indicating a time interval during which an LDM Data Object is valid
2 © ISO 2018 – All rights reserved

ISO 18750:2018(E)
3.12
LDM Time of Interest
time requirement used in the filter process of queries and automatic notifications
3.13
Local Dynamic Map
entity consisting of LDM Data Objects, services and interfaces for manipulating these LDM Data Objects
3.14
location reference
uniquely identifiable description of position or area in the real world
3.15
metadata
data about data
Note 1 to entry: The term "metadata" is ambiguous as it is used for fundamentally different concepts. Structural
metadata is information related to the design and specification of data structures; it is also referred to as "data
about the containers of data". Descriptive metadata is information on instances of data, i.e. the data content; it is
also referred to as "data about data content".
3.16
Time of Creation
time when an LDM Data Record was created and updated
3.17
Time of Deletion
time when an LDM Data Record may be deleted and will no longer be considered by the LDM search
functionality
3.18
Time of Generation
time when the content of the LDM Data Object information field was created
Note 1 to entry: This is different to the time, when the LDM Data Object was written into an LDM.
4 Symbols and abbreviated terms
BSMD Bounded Secured Managed Domain
BSME Bounded Secured Managed Entity
IAT International Atomic Time
ICS Implementation Conformance Statement
ITS Intelligent Transport Systems
ITS-SCU ITS Station Communication Unit
ITS-SU ITS Station Unit
IUT Implementation Under Test
LDM Local Dynamic Map
LDM-DD LDM Data Dictionary
LDM-DT LDM Data Type
ISO 18750:2018(E)
LDM-DAT LDM Data Attribute Type
LDM-DATID LDM-DAT Identifier
LDM-DTID LDM-DT Identifier
NoO Notification of Obligations
OoT Obligation of Trust
PMI Privilege Management Infrastructure
SAO Signed Acceptance of Obligations
SUT System Under Test
TPEG Transport Protocol Experts Group
UTC Universal Time Coordinated
5 Architectural environment
This clause contains informative descriptions of the architectural environment of an LDM.
5.1 Local Dynamic Map
A Local Dynamic Map (LDM) is an entity consisting of LDM Data Objects, services and interfaces for
manipulating these LDM Data Objects (LDM-DO). LDM-DOs are distinguished by means of their LDM
Data object Type (LDM-DT). LDM-DTs are specified by registration in an LDM Data Dictionary (LDM-
DD). The concept of the LDM-DD is specified in Annex B.
[18]
NOTE In ISO TR 17424 , LDM-DOs are classified into Type 1 (static permanent data objects, e.g.
[2]
cartographic data), Type 2 (static transitory data objects, e.g. temporary parking lot on the road), Type 3
(dynamic transitory data objects, e.g. works location), and Type 4 (highly dynamic data objects, e.g. location,
orientation and speed of surrounding vehicles). This classification is not used in this document.
An LDM-DO provides information on real objects (cars, road events, .) that exist at a defined location,
e.g. in a defined geo-area, and within a defined time interval. In the uppermost simple case the
information provided by an LDM-DO is just its type, its geo-location, and its time interval of validity.
Such information may be received in an ITS station unit via different channels such as:
[34] [38]
— DATEX II , TPEG , RDS-TMC (legacy systems);
[19] [20] [28]
— CEN / ETSI / ISO / SAE ITS Message sets EN/ISO 19091 , ISO/TS 19321 , ETSI EN 302 637-2 ,
[29] [39]
ETSI EN 302 637-3 , SAE J2735 ;
composed of different sets of attributes, and presented in different formats (encodings). ITS-S
application processes capable to receive this information perform a mapping on LDM-DOs and a
translation of attribute formats into the common format given by the LDM-DTs.
5.2 LDM in an ITS-S
The local dynamic map (LDM) specification provided in this document is designed for the architectural
environment of an ITS station operated as a Bounded Secured Managed Domain (BSMD) specified in
ISO 21217 and illustrated in Figure 1.
4 © ISO 2018 – All rights reserved

ISO 18750:2018(E)
Figure 1 — LDM in an ITS-S operated as a Bounded Secured Managed Domain (BSMD)
The LDM functionality specified in Clause 6 is located in the ITS-S facilities layer. An LDM interfaces
with ITS-S application processes specified in ISO 21217. The interface functionality is specified in 6.6.2
by means of functions of services of the FA-SAP and the MF-SAP; both Service Access Points (SAPs)
offer identical functions for this purpose. The generic services of FA-SAP and MF-SAP are specified in
[11]
ISO 24102-3 .
5.3 LDM in an ITS-SU
Various examples of supported implementation configurations are illustrated in Figure 2, Figure 3,
Figure 4, and Figure 5.
Figure 2 illustrates a "single-box" configuration of an ITS station unit (ITS-SU) with a single LDM.
Figure 2 — Implementation configuration example a)
Figure 3 illustrates a "single-box" configuration of an ITS-SU with two LDMs.
ISO 18750:2018(E)
Figure 3 — Implementation configuration example b)
Figure 4 illustrates a configuration of an ITS-SU with two ITS station communication units (ITS-SCU).
One of these ITS-SCUs has a host-only role specified in ISO 21217 and contains a single LDM. The other
ITS-SCU has a router-only role specified in ISO 21217 and does not contain an LDM.
Figure 4 — Implementation configuration example c)
Figure 5 illustrates a configuration of an ITS-SU with two ITS station communication units (ITS-SCU).
One of these ITS-SCUs has a host-only role specified in ISO 21217 and contains a single LDM. The other
ITS-SCU has a host-and-router role specified in ISO 21217 and contains also an LDM.
6 © ISO 2018 – All rights reserved

ISO 18750:2018(E)
Figure 5 — Implementation configuration example d)
Many other implementation configurations are feasible.
NOTE In ITS-SUs composed of several ITS-SCUs the ITS station management can use the "ITS station-
[12]
internal management communications protocol" (IICP) specified in ISO 24102-4 to support overall station
management.
5.4 LDM related processes
5.4.1 Synchronization of LDMs
[18]
The concept of synchronization of LDMs is introduced in ISO TR 17424 , distinguishing:
— synchronization of LDMs operated in ITS station units of different vehicles;
— synchronization of LDMs operated in ITS station units at the roadside, in central offices and in
vehicles.
Reference is made to means which are already in use for TPEG and DATEX.
Such synchronization means updating of an LDM by an authorized "master" LDM. As only ITS-S
application processes can access LDM-DOs, any synchronization is to be realized by ITS applications.
Details are outside the scope of this document.
NOTE Updates of information in an ITS-SU can be performed using remote management standardized in
[10]
ISO 24102-2 .
5.4.2 Archiving of LDM Data Objects
Archiving of LDM Data Objects is a feature that produces a kind of log-file of an LDM. Such log-
file information might be of interest for different purposes, but might also be subject to privacy
considerations.
This document specifies neither an archiving functionality nor related interfaces. Archiving can be
implemented in a non-standardized way.
5.5 LDM for road safety and vehicle-to-vehicle applications
An LDM dedicated to usage for road safety and vehicle-to-vehicle applications (electronic horizon) is
[30]
specified by ETSI in EN 302 895 . This ETSI LDM specification constitutes a functional sub-set of the
specification provided in this document.
ISO 18750:2018(E)
5.6 Security perspective
5.6.1 Authorised access to LDM
The architecture of an LDM in the context of BSMD from a security perspective is to ensure that access is
restricted to identified and authorised ITS-S application processes. Application processes not certified
for operation in a BSMD may access an LDM via a secure gateway described in ISO 21217, where the
firewall ITS-S application process of this gateway is authorised for read-access to the LDM.
All the core assets are to be considered as vulnerable and therefore subject to protection, where
protection takes the form of specific guards. The guard mechanism used in protecting the LDM is a
policy based access control scheme where ITS-S application processes will pre-register their policy
with the ITS-S and if that policy is agreed all future access by the ITS-S application process will be
verified as being consistent with the policy.
5.6.2 Initialisation and installation of applications to the BSMD
The kernel of an ITS-SCU forms a trust centre of the BSME and is identifiable to third party ITS-S
application processes as such. Any ITS-S application process to be added to an ITS-SCU within the
BSME verifies the identity and capability of the ITS-SCU prior to installation. If installation is allowed
an ITS-SCU verifies the credentials offered by the ITS-S application process. Prior to distribution each
ITS-S application process is functionally verified and tested and assertions of required functionality, of
[21]
developer identity, and of the tester, are validated prior to installation ISO 17419 .
[41]
The core model follows that developed in the i-Tour project as an extension of an "Obligation of
Trust" (OoT) protocol, extending the models used for Java midlet distribution used in many common
[21]
application stores, see ISO 17419 . The protection framework is a form of a Privilege Management
Infrastructure (PMI) based on common cryptographic modules and processing where authorisation
is viewed as a set of mutually agreed actions through the assignment of permissions to the parties,
i.e. the LDM and the LDM user. In the OoT protocol the participating parties exchange difficult-to-
repudiate digitally signed obligating constraints, also referred to as "Notification of Obligations" (NoO),
which detail their requirements for sending their sensitive information to the other party, and proof
of acceptances, also referred to as "Signed Acceptance of Obligations" (SAO), which acknowledge the
conditions they have accepted for receiving the other party’s sensitive information. The required
capabilities of the LDM user, i.e. an ITS-S application process, to be installed will be declared and the
application restricted to use only those capabilities by means of a policy enforcement engine acting in
the role of a Policy Enforcement Point in the LDM itself.
For protection of data the data objects identified below capture the primary policy elements
PrivacyPolicyDirective, SecurityPolicyDirective, SignedPrivacyPolicy, SignedSecurityPolicy,
CounterSignedPrivacyPolicy, and CounterSignedSecurityPolicy.
The privacy policy directive is a set of policy statements that identify the identity of the data controller.
The privacy enforcement point agrees to implement the policy and to indicate that in the Signed Privacy
Policy where the signature is of the data processor (acting as policy enforcement point).
Acceptance of the privacy policy is notified by the client in the Countersigned Privacy Policy where
the signature is given by the client using the pseudonymous identity agreed during registration. The
retention of the countersigned policy agreement provides the basis of non-repudiation of consent.
NOTE The data privacy legislation in Europe assumes the presence of a number of entities in a system dealing
with private data. These are the data controller, data processor and data subject, and a contract of consent. In an
all informed C-ITS there is no a priori consent establishment between the transmitting ITS-SU and any of the
receiving ITS-SUs, thus the security model attempts to minimize the possibility of any personal data being made
known to a receiving ITS-SU. The model therefore virtualizes the functionality of data controller, data processor
and consent by use of verifiable proofs of authority to act on data.
Permissions resulting from policy are of type "Permit" and "Deny" based on authorization, i.e. after
application of the policy the request is either permitted or denied. Requests themselves may contain
specific access requests, e.g. read data from the LDM, write data to the LDM.
8 © ISO 2018 – All rights reserved

ISO 18750:2018(E)
Every incoming command to the LDM is associated with a set of claims that are checked against the local
policy at the PEP in the LDM. If any data access attempt from an application is made post-registration
and post-acceptance of the policy that does not comply with the policy it is denied.
5.6.3 Privacy
The C-ITS enforces pseudonymity capabilities through the security functions described, e.g. in
[32] [33]
ETSI TS 102 940 and ETSI TS 102 941 which maintains privacy control of data entered into
the LDM.
5.7 An LDM versus other similar functionalities in an ITS-SU
The sharing of data between ITS-S application processes in an ITS-SU can be achieved by subscribe/
publish mechanisms, where at least two mechanisms are distinguished, i.e.
a) one allowing ITS-S application processes to subscribe at the ITS-S facilities layer to standardized
[22]
messages from ITS message sets as specified in ISO/TS 17429 without using an LDM, and
b) one using a local dynamic map (LDM) as repository of standardized data objects.
[22]
The approach a) specified in ISO/TS 17429 standardizes an ITS-S facility layer message handler
which can
— directly forward complete received messages to subscribed ITS-S application processes without
storing these messages, and
— present LDM Data Objects to an LDM in case these LDM Data Objects are contained in messages that
follow the message format convention of this message handler.
There may be also other data storages, which are basically different to an LDM, i.e. which may store
data objects that are not following the definition of an LDM-DO.
6 Functionality
This clause contains informative descriptions of the functionality of an LDM.
6.1 Terms and conventions
As explained in 5.1, an LDM deals with information on real objects that are existent at a defined location
(geo-area) and within a defined time interval. Such information on a real object is identified in an LDM
Data Record, see Figure 7. Every LDM Data Record is identified with a unique LDM Data Record ID; the
value zero indicates an "unknown record".
Different location and time definitions are used to define the functionality of an LDM.
— Definitions related to the information on the real object
— Location Validity
Information at which geo-location or in which geo-area the LDM-DO applies.
— Time Validity
Information in which time interval(s) the LDM-DO applies.
— Time of Generation
Information on the time when the LDM-DO information was generated, e.g. time when a
perception system (e.g. a sensor) detected the event "slippery road".
ISO 18750:2018(E)
— Time of Mandatory Deletion
Information on time after which the LDM record will no longer be returned in a query.
— Definitions used in queries
— LDM Area of Interest
Geo-location(s) or geo-area(s) that are of interest for the querying ITS-S application process.
— LDM Time of Interest
Time instant or time interval(s) that are of interest for the querying ITS-S application process.
— Age of Interest
Age of LDM record as required by the querying ITS-S application process. The age is
calculated with a numerical operator presented by the ITS-S application process against the
time of generation of an LDM-DO, if available, or alternatively against the time of last update
of an LDM-DO.
— Definitions used for maintenance purposes
— LDM Area of Maintenance
Geo-area(s) considered by the LDM search functionality and defined by the LDM in an
implementation-specific way. Without overlap of the LDM Area of Interest with the LDM Area
of Maintenance a query will not result in a hit. Note that the area of maintenance can be defined
relative to the momentary location of the host ITS-S.
— LDM Inactive Area
Geo-area(s) considered by the LDM to store LDM records with are not considered by the search
functionality; there is no overlap between the LDM Area of Maintenance and the LDM Inactive
Area. Details on the usage of the LDM Inactive Area are not specified in this document.
— Time of Creation
Time at which the LDM record was created in the LDM Data Storage.
— Time of Deletion
Time after which an LDM record may be deleted, and will no more be considered by the LDM
search functionality.
Several location reference systems and time reference systems are known; examples are presented in
Annex D and Annex E. This document supports any kind of reference system by defining time reference
and location reference with the ASN.1 type CLASS which allows defining specific instantiations at a
later time according to the needs of C-ITS services. The generic approach for location is given in the
ASN.1 type LDMarea. The generic approach for time is given in the ASN.1 type TimeInformation.
In order to manage time an LDM needs to maintain or access a time reference system (clock). This
document assumes that there is a trusted time service available in an ITS-SU which can be used in
an implementation specific way. Time synchronization with an external clock to ensure unique time
information in all ITS-SUs will be a task of the ITS-S management of an ITS-S facility, e.g. as specified in
[23]
ISO 21176 .
Similarly it is assumed that an LDM has access to a service providing continuously the kinematic state of
the ITS-SU in which it resides; thus no explicit interface to such a service is specified in this document.
10 © ISO 2018 – All rights reserved

ISO 18750:2018(E)
As this document supports various implementation architectures illustrated in 5.3, ITS-S application
processes need to be enabled to select appropriate LDMs. For this purpose,
a) LDMs are identified by an LDM ID that is unique in an ITS-SU,
b) LDMs register at the ITS-S management entity reporting about their capabilities in terms of
supported LDM-DOs, and
c) ITS-S application processes register at the ITS-S management entity reporting their LDM
requirements in terms of required LDM-DOs, which is acknowledged by providing the address
information of the best suited LDMs.
The LDM performs the following procedures to maintain integrit
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