Electronic fee collection - Secure monitoring for autonomous toll systems - Part 2: Trusted recorder

This document defines the requirements for the secure application module (SAM) used in the secure monitoring compliance checking concept. It specifies two different configurations of a SAM:
-   trusted recorder, for use inside an OBE;
-   verification SAM, for use in other EFC system entities.
This document describes
-   terms and definitions used to describe the two Secure Application Module configurations;
-   operation of the two Secure Application Modules in the secure monitoring compliance checking concept;
-   functional requirements for the two Secure Application Modules configurations, including a classification of different security levels;
-   the interface, by means of transactions, messages and data elements, between an OBE or Front End and the trusted recorder;
—   requirements on basic security primitives and key management procedures to support Secure Monitoring using a trusted recorder.
This document is consistent with the EFC architecture as defined in FprEN ISO 17573-1 and the derived suite of standards and Technical Specifications, especially FprCEN/TS 16702-1 and CEN ISO/TS 19299.
The following is outside the scope of this document:
-   The life cycle of a Secure Application Module and the way in which this is managed;
-   The interface commands needed to get a Secure Application Module in an operational state;
-   The interface definition of the verification SAM;
-   Definition of a hardware platform for the implementation of a Secure Application Module.

Elektronische Gebührenerhebung - Sichere Überwachung von autonomen Mautsystemen - Teil 2: Zuverlässige Datenaufzeichnung

Perception du télépéage - Surveillance sécurisée pour systèmes autonomes de péage - Partie 2: Enregistreur fiabilisé

Elektronsko pobiranje pristojbin - Varnostno spremljanje avtonomnih cestninskih sistemov - 2. del: Zaupanja vreden snemalnik

Ta dokument določa zahteve za modul varnega dostopa (SAM), ki se uporablja pri konceptu preverjanja skladnosti varnostnega spremljanja. Določa dve različni konfiguraciji modula varnega dostopa:
– zaupanja vreden snemalnik: za uporabo v opremi v vozilu (OBE);
– modul varnega dostopa za preverjanje: za uporabo v drugih entitetah sistema za elektronsko pobiranje pristojbin (EFC).
Ta dokument podaja:
– izraze in definicije, ki so uporabljeni za opis teh dveh konfiguracij modula varnega dostopa;
– delovanje teh dveh modulov varnega dostopa v konceptu preverjanja skladnosti varnostnega spremljanja;
– funkcionalne zahteve za ti dve konfiguraciji modula varnega dostopa, vključno z razvrstitvijo različnih varnostnih ravni;
– vmesnik, prek transakcij, sporočil in podatkovnih elementov, med opremo v vozilu ali čelnim delom in zaupanja vrednim snemalnikom;
– zahteve glede osnovnih varnostnih primitivov in ključnih postopkov upravljanja kot podpora varnostnemu spremljanju z uporabo zaupanja vrednega snemalnika.
Ta dokument je v skladu z arhitekturo za elektronsko pobiranje pristojbin, kot je določena s standardom FprEN ISO 17573-1 in skupino izpeljanih standardov in tehničnih specifikacij, še posebej FprCEN/TS 16702-1 in CEN ISO/TS 19299.
Naslednje ne spada na področje uporabe tega dokumenta:
– življenjska doba modula varnega dostopa in način, na katerega se to upravlja;
– ukazi vmesnika, ki so potrebni za zagon modula varnega dostopa;
– definicija vmesnika modula varnega dostopa za preverjanje;
– definicija platforme za strojno opremo za izvajanje modula varnega dostopa

General Information

Status
Published
Publication Date
03-Feb-2020
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
04-Feb-2020
Due Date
10-Apr-2020
Completion Date
04-Feb-2020

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SLOVENSKI STANDARD
SIST-TS CEN/TS 16702-2:2020
01-marec-2020
Nadomešča:
SIST-TS CEN/TS 16702-2:2015
Elektronsko pobiranje pristojbin - Varnostno spremljanje avtonomnih cestninskih
sistemov - 2. del: Zaupanja vreden snemalnik
Electronic fee collection - Secure monitoring for autonomous toll systems - Part 2:
Trusted recorder
Elektronische Gebührenerhebung - Sichere Überwachung von autonomen
Mautsystemen - Teil 2: Zuverlässige Datenaufzeichnung
Perception du télépéage - Surveillance sécurisée pour systèmes autonomes de péage -
Partie 2: Enregistreur fiabilisé
Ta slovenski standard je istoveten z: CEN/TS 16702-2:2020
ICS:
03.220.20 Cestni transport Road transport
35.240.60 Uporabniške rešitve IT v IT applications in transport
prometu
SIST-TS CEN/TS 16702-2:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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CEN/TS 16702-2
TECHNICAL SPECIFICATION

SPÉCIFICATION TECHNIQUE

January 2020
TECHNISCHE SPEZIFIKATION
ICS 03.220.20; 35.240.60 Supersedes CEN/TS 16702-2:2015
English Version

Electronic fee collection - Secure monitoring for
autonomous toll systems - Part 2: Trusted recorder
Perception du télépéage - Surveillance sécurisée pour Elektronische Gebührenerhebung - Sichere
systèmes autonomes de péage - Partie 2 : Enregistreur Überwachung von autonomen Mautsystemen - Teil 2:
fiabilisé Zuverlässige Datenaufzeichnung
This Technical Specification (CEN/TS) was approved by CEN on 25 November 2019 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to
submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS
available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in
parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, 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
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 16702-2:2020 E
worldwide for CEN national Members.

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Contents Page

European foreword . 4
Introduction . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Symbols and abbreviations . 12
5 SAM concept and scenarios . 13
5.1 General . 13
5.2 The concepts of TR and verification SAM . 13
5.3 Scenarios for a trusted recorder. 15
5.3.1 General . 15
5.3.2 Real-Time Freezing without using a Trusted Time Source . 15
5.3.3 Real-Time Freezing using a Trusted Time Source . 16
5.4 Scenarios for a verification SAM . 16
5.4.1 General . 16
5.4.2 MAC verification . 16
5.5 General Scenarios . 17
5.5.1 General . 17
5.5.2 Assigning a Toll Domain Counter . 17
5.5.3 Obtaining SAM Information . 18
6 Functional requirements. 19
6.1 General . 19
6.1.1 SAM options . 19
6.1.2 Presentation of requirements . 20
6.2 Basic requirements . 20
6.3 Key management . 21
6.4 Cryptographic functions . 21
6.5 Real-time freezing . 22
6.6 Verification SAM . 23
6.7 Toll Domain Counter . 23
6.8 Trusted time source . 24
6.9 Security protection level . 25
7 Interface requirements . 26
7.1 General . 26
7.2 Calculate MAC for real-time freezing . 26
7.2.1 General . 26
7.2.2 Calculation of MAC . 27
7.2.3 Coding of request . 27
7.2.4 Coding of response. 28
7.3 Calculate digital signature for real-time freezing . 28
7.3.1 General . 28
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7.3.2 Calculation of digital signature . 29
7.3.3 Coding of request . 29
7.3.4 Coding of response . 29
7.4 Get device information . 30
7.4.1 General . 30
7.4.2 Coding of request . 30
7.4.3 Coding of response . 31
7.5 Get toll domain counter information. 31
7.5.1 General . 31
7.5.2 Coding of request . 31
7.5.3 Coding of response . 32
7.6 Get key information . 32
7.6.1 General . 32
7.6.2 Coding of request . 33
7.6.3 Coding of response . 33
7.7 Error handling . 34
Annex A (normative) Data type specification . 35
Annex B (normative) Implementation Conformance Statement (ICS) proforma . 36
Annex C (informative) Trusted Time Source implementation issues. 49
Annex D (informative) Use of this document for the EETS . 51
Bibliography . 53


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European foreword
This document (CEN/TS 16702-2:2020) has been prepared by Technical Committee CEN/TC 278
“Intelligent transport systems”, the secretariat of which is held by NEN.
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/TS 16702-2:2015.
The CEN/TS 16702 series, Electronic fee collection – Secure monitoring for autonomous toll systems, is
composed with the following parts:
— Part 1: Compliance checking;
— Part 2: Trusted recorder.
This document about the trusted recorder is the second part of the CEN/TS 16702 series about the secure
monitoring for autonomous toll systems. The overall concept of secure monitoring is defined in
CEN/TS 16702-1.
This second edition will supersede the first edition (CEN/TS 16702-2:2015), which was technically
revised. The main changes compared to the previous edition are as follows:
— references to underlaying standards updated to latest version;
— updated terminology;
— slight restructuring.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United
Kingdom.
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Introduction
The widespread use of tolling requires provisions for users of vehicles that are roaming through many
different toll domains. Users should be offered a single contract for driving a vehicle through multiple toll
domains and those vehicles require on-board equipment (OBE) that is interoperable with the toll systems
in these toll domains. Thus, there is a commercial and economic justification both in respect of the OBE
and the toll systems for supporting interoperability. In Europe, for example, this need is recognized and
legislation on interoperability has been adopted (see Directive 2004/52/EC) and the associated
Commission Decision.
CEN ISO/TS 19299, Electronic fee collection – Security framework (ISO/TS 19299), provides an overview
of general security requirements of the stakeholders and provides a comprehensive threat analysis for
the assets in an interoperable EFC scheme. Security attacks may result into less revenue of the toll
charger, undercharging or not meeting required service levels between the toll service provider and the
toll charger. Some of these threats can be eliminated by implementing the security measures that are
specified. However, most of the security measures necessary to combat the identified threats are
addressed and specified in other standards.
One example of threats that cannot be mitigated by security measures specified in CEN ISO/TS 19299
concerns the trustworthiness of Toll Declarations in autonomous toll systems. Toll declarations are
statements that a vehicle has been circulating in a particular toll domain within a particular time period.
In autonomous toll systems, the circulation of vehicles is measured by toll service providers, using GNSS-
based OBE. Toll service providers then send Toll Declarations to the toll charger, based on which the toll
charger will charge the toll service provider. The correctness and completeness of these declarations are
obviously of paramount interest to toll chargers, toll service providers and users alike.
The secure monitoring compliance checking concept provides a solution that allows a toll charger to
check the trustworthiness of the Toll Declarations from a toll service provider, whilst respecting the
privacy of the user. This concept is defined in the CEN/TS 16702 series:
• CEN/TS 16702-1, Electronic fee collection – Secure monitoring for autonomous toll systems – Part 1:
Compliance checking, which defines the secure monitoring compliance checking concept;
• CEN/TS 16702-2, Electronic fee collection – Secure monitoring for autonomous toll systems – Part 2:
Trusted recorder (this document), which defines the trusted recorder, a secure element required for
some of the different types of secure monitoring compliance checking concepts.
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Figure 1 — Relation between EFC – Security framework and the overall secure monitoring
concept
Figure 1 shows the relations between CEN ISO/TS 19299, Electronic fee collection – Security framework,
and the CEN/TS 16702 series. The threat analysis in the Security Framework motivates the security
requirements of an EFC system. The requirements are implemented and fulfilled by several security
measures. One of these measures is Secure Monitoring, specified in CEN/TS 16702-1, which defines the
cryptographic services necessary for the secure monitoring compliance checking concept.
Figure 1 indicates also that a trusted recorder will most likely be implemented on trusted hardware,
e.g. on Secure Application Module (SAM), inside the OBE or on a general trusted platform of a vehicle.
Such a trusted device could support more functions, which may be required for EFC or other services.
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1 Scope
This document defines the requirements for the secure application module (SAM) used in the secure
monitoring compliance checking concept. It specifies two different configurations of a SAM:
— trusted recorder, for use inside a piece of on-board equipment (OBE);
— verification SAM, for use in other EFC system entities.
This document describes
— terms and definitions used to describe the configurations of the two SAMs;
— operation of the two SAMs in the secure monitoring compliance checking concept;
— functional requirements for the configurations of the two SAMs, including a classification of different
security levels;
— the interface, by means of transactions, messages and data elements, between an OBE or front end
and the trusted recorder;
— requirements on basic security primitives and key management procedures to support Secure
Monitoring using a trusted recorder.
This document is consistent with the EFC architecture as defined in EN ISO 17573-1 and the derived suite
of standards and Technical Specifications, especially CEN/TS 16702-1 and CEN ISO/TS 19299.
The following is outside the scope of this document:
— The life cycle of a SAM and the way in which this is managed;
— The interface commands needed to get a SAM in an operational state;
— The interface definition of the verification SAM;
— Definition of a hardware platform for the implementation of a SAM.
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.
CEN/TS 16702-1:2020, Electronic fee collection - Secure monitoring for autonomous toll systems - Part 1:
Compliance checking
CEN ISO/TS 19299:2015, Electronic fee collection – Security framework (ISO/TS 19299)
EN ISO 14906, Electronic fee collection - Application interface definition for dedicated short-range
communication (ISO 14906)
ISO/IEC 7816-4:2013, Identification cards — Integrated circuit cards — Part 4: Organization, security and
commands for interchange
ISO/IEC 8825-2, Information technology — ASN.1 encoding rules: Specification of Packed Encoding Rules
(PER) — Part 2:
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ISO/IEC 9797-1, Information technology — Security techniques — Message Authentication Codes (MACs)
— Part 1: Mechanisms using a block cipher
ISO/IEC 10118-3, IT Security techniques — Hash-functions — Part 3: Dedicated hash-functions
ISO/IEC 18031, Information technology — Security techniques — Random bit generation
ISO/IEC 18033-3, Information technology — Security techniques — Encryption algorithms — Part 3: Block
ciphers
ISO/IEC 19790:2012, Information technology — Security techniques — Security requirements for
cryptographic modules
FIPS PUB 140-2, December 2002, Security requirements for cryptographic modules
Common Criteria Protection Profile BSI-PP-0035, 2007, Security IC Platform Protection Profile,
Version 1.0
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 http://www.iso.org/obp
3.1
authentication
security mechanism allowing the verification of the provided identity
[SOURCE: EN 301 175 V1.1.1 (1998-08), Clause 3]
3.2
authenticator
data, possibly encrypted, that is used for authentication
[SOURCE: EN 15509:2014, 3.3]
Note 1 to entry: In this CEN/TS either a MAC or a signature.
3.3
authenticity
property that an entity is what it claims to be
[SOURCE: CEN ISO/TS 19299:2015, 3.5]
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3.4
back end
part of a back office system interfacing to one or more front ends
[SOURCE: CEN ISO/TS 19299:2015, 3.7, modified — "back end" and "front end" originally had upper-case
characters.]
3.5
big-endian
format for transmission of binary data in which the most significant byte appears first
[SOURCE: ISO/IEC 14776-262:2017, 3.1.18, modified]
3.6
confidentiality
prevention of information leakage to non-authenticated individuals, parties or processes
[SOURCE: CEN ISO/TS 19299:2015, 3.11, modified — "and/or processes" was replaced with "or
processes".]
3.7
data integrity
property that data has not been altered or destroyed in an unauthorized manner
[SOURCE: ISO 7498-2:1989, 3.3.21]
3.8
digital signature
one or more data elements resulting from the digital signature process
[SOURCE: CEN ISO/TS 19299:2015, 3.11, 3.38]
3.9
front end
part of a tolling system consisting of on-board equipment (OBE) and possibly a proxy where road tolling
information and usage data are collected and processed for delivery to the back end
[SOURCE: CEN ISO/TS 19299:2015, 3.17, modified — "back end" and "front end" originally had upper-
case characters.]
3.10
itinerary
travel diary organized in one or more itinerary records enabling assessment of the correctness of the toll
declaration
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3.11
message authentication code
MAC
fixed-length string of bits used to verify the authenticity of a message, generated by the sender of the
message, transmitted together with the message, and verified by the receiver of the message
[SOURCE: ISO 16609:2012, 3.15]
Note 1 to entry: A MAC is sometimes called a cryptographic check value (see for example ISO 7498-2).
3.12
non-repudiation
ability to prove the occurrence of a claimed event or action and its originating entities
[SOURCE: CEN ISO/TS 19299:2015, 3.27]
3.13
on-board equipment
OBE
required equipment on-board a vehicle for performing required electronic fee collection (EFC) functions
and communication services
3.14
real-time freezing
freezing of each itinerary record as soon as its acquisition has terminated, using a trusted recorder
3.15
roadside equipment
RSE
equipment located along the road, either fixed or mobile
3.16
Secure Application Module
SAM
physical module that securely executes cryptographic functions and stores keys
[SOURCE: CEN ISO/TS 19299:2015, 3.35]
3.17
secure monitoring compliance checking
concept that allows a toll charger to rely on the trustworthiness of toll declarations produced by toll
service providers
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3.18
time lock
mechanism ensuring that a new operation can only be commissioned after a configurable period of time
or processor clock cycles since the previous operation
3.19
TR issuer
institution (or its agent) that issues the trusted recorder
[SOURCE: ISO/IEC 7812-1:2006, 3.3, adapted]
3.20
toll charger
TC
entity which levies toll for the use of vehicles in a toll domain
3.21
toll declaration
statement to declare the usage of a given toll service to a toll charger
[SOURCE: CEN ISO/TS 19299:2015, 3.44]
3.22
toll domain
area or a part of a road network where a certain toll regime is applied
3.23
toll domain ID
unique identifier of a toll domain
3.24
toll service
service enabling users to pay toll
3.25
toll service provider
TSP
entity providing toll services in one or more toll domains
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3.26
trusted recorder
TR
logical entity capable of cryptographic functions, used to provide the on-board equipment (OBE) with
security services, including data confidentiality, data integrity, authentication and non-repudiation
3.27
Trusted Third Party
TTP
security authority, or its agent, trusted by other entities with respect to security related activities
[SOURCE: ISO/IEC 10181-1:1996, 3.3.30, modified]
3.28
toll service user
customer of a toll service provider, i.e. one liable for toll, owner of the vehicle, fleet operator or driver
depending on the context
Note 1 to entry: This is a generic term which is context dependent.
3.29
verification SAM
Secure Application Module capable of providing cryptographic services to verify a trusted recorder MAC
in such manner that the proof of non-repudiation is given
4 Symbols and abbreviations
ADU Application Data Unit
AES Advanced Encryption Standard
APDU Application Protocol Data Unit
BCD Binary Coded Decimal
CA Certification Authority
CLA Class byte
CMAC Cipher-based MAC
ECC Elliptic Curve Cryptography
ECDSA Elliptic Curve Digital Signature Algorithm
EETS European Electronic Toll Service
GNSS Global Navigation Satellite System
ID Identifier
INS Instruction byte
KVC Key Verification Code
MAC Message Authentication Code
NTP Network Time Protocol
OBE On-Board Equipment
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P1, P2 Parameter bytes
PKI Public Key Infrastructure
PP Protection Profile
RQ Requirement
RSA Algorithm for public-key cryptography (Rivest, Shamir and Adleman)
RSE Roadside Equipment
SAM Secure Application Module
SNTP Simple Network Time Protocol
TC toll charger
TDC Toll Domain Counter
TR trusted recorder
TRID trusted recorder Identifier
TSP toll service provider
TTP Trusted Third Party
TTS Trusted Time Source
UTC Coordinated Universal Time
5 SAM concept and scenarios
5.1 General
CEN/TS 16702-1 defines requirements for a trusted recorder (TR) used in a piece of OBE, which supports
symmetric and asymmetric algorithms. A verification SAM (for example in the RSE) is required to achieve
the same cryptographic proof of non-repudiation when using the symmetric algorithm compared to the
asymmetric algorithm. Subclause 6.2 of this document describes the two different configurations of the
SAM in the EFC context.
Subclauses 6.3, 6.4 and 6.5 describe the scenarios for the use of the TR and verification SAM, motivated
by CEN/TS 16702-1 (variations SM_CC-1 “Real-time Freezing using a TR without trusted time source”
and SM_CC-2 “Real-time Freezing using a TR with trusted time source”). The scenarios in these clauses
cover all possible use cases for both SAM configurations, a TR inside an OBE and a verification SAM used
in the RSE or another EFC entity.
NOTE Names and data flow elements in the diagrams in Clause 6 are symbolic and do not always give all details.
For details, refer to Clause 8.
5.2 The concepts of TR
...

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