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PT1605 is a standard development project funded by the European Commission under grant agreement SA/CEN/GROW/EFTA/453/2016-11. CEN reports about the PT1605 work on its special PT web page.

An introduction in the work of PT1605 is presented in the first newsletter from PT1605.

You can reach the PT members by email.

PT1605 complements the set of standards for C-ITS by providing the following deliverables:

  • CEN/TS 21176 (under VA), Cooperative intelligent transport systems (C-ITS) - Position, velocity and time functionality in the ITS station
  • CEN/TS 21177 (under VA), Intelligent transport systems - ITS security services for secure session establishment and authentication between trusted devices
  • CEN/TS 21184 (under VA), Cooperative intelligent transport systems (C-ITS) - Global transport data management (GTDM) framework
  • CEN/TS 17496 (almost identical with ISO/TS 21185), Cooperative intelligent transport systems (C-ITS) - Communication profiles
  • CEN/TR 21186 (under VA), Cooperative intelligent transport systems (C-ITS) - Guidelines for the usage of standards -
    Part 1: Standardization landscape and releases
    Part 2: Hybrid communications
    Part 3: Security

    Final ballot ends on 31.12.2020!


Introduction to C-ITS standards

A detailed general introduction to C-ITS standards will be published soon. Below an exerpt:

There is a "family" of deliverables from "Standard Development Organizations" (SDOs) for "Cooperative Intelligent Transport Systems" (C-ITS), which is a subset of standards for "Intelligent Transport Systems" (ITS).

ITS aims on improving surface transportation in respect of

  • safety e.g.: crash avoidance, obstacle detection, emergency call, dangerous goods;
  • efficiency e.g. navigation, green wave, priority, lane access control, contextual speed limits, car sharing;
  • comfort e.g. telematics, parking, electric vehicle charging, infotainment;
  • sustainability, by applying information and communication technologies (ICT).

ITS specifications are in general developed to address a specific ITS service domain such as public transport, road safety, freight and logistics, public emergency, electronic fee collection.

To support interoperability, C-ITS specifications are developed to exchange and share information ITS applications of a given application domain, and even between application domains.

C-ITS services are based on the exchange of data between vehicles of any category (cars, trucks, buses, emergency and specialized vehicles, ...), the roadside and urban infrastructure (traffic lights, road tolls, variable message signs, ...), control and services centres in the cloud (traffic control centre, service providers, map providers, …), and other road users (pedestrians, cyclists, …).

Some ITS services require cooperation by vehicles with their surrounding environment (other vehicles, other road users, roadside and urban infrastructure, …) while other ITS services require connectivity to remote service platforms (road traffic control centres, map providers, service providers, fleet managers, equipment manufacturers, …).

To support

  • a large variety of C-ITS services with diverging requirements, and
  • efficient sharing of information maintained by individual service applications,

it is necessary to combine multiple access technologies and communication protocols with distinct performance characteristics (communication range, available bandwidth, end-to-end transmission delay, quality of service, security, ...).

Combining multiple access technologies and communication protocols requires a common approach to the way communications and data are managed in a secure way. A functional architecture (“the ITS station architecture”) is thus specified to manage security, communications and data related to C-ITS services.

The ITS station architecture is specified in ISO 21217, and details of functional building blocks of the ITS station architecture are specified in a set of related standards.

Similar to the ISO Open Systems Interconnection (OSI) 7-layer architecture, the ITS station architecture is designed into three independent communication layers (namely the ITS station access layer, the ITS station networking & transport layer, and the ITS station facilities layer) on top of which the ITS Applications entity is located. Additional cross-layer entities in charge of the management activities (management of ITS station units, communications and security) are supporting communications and applications.

An implementation of this ITS station architecture is referred to as "ITS Station Unit) (ITS-SUs); see ISO 21217. The functionalities available in an ITS station unit can be implemented in one or multiple physical units referred to as "ITS Station Communication Units" (ITS-SCUs); even such that the various ITS-SCUs of one ITS-SU are split over a large geographical area, e.g. along a motorway with several 10kms length.

ITS-SUs compliant with ISO 21217 can be deployed in various environments, including vehicles of any kind (vehicle ITS station), on the roadside infrastructure (roadside ITS station), in the cloud (central ITS station) or in nomadic devices (personal ITS station).

As C-ITS deals with safety of human life and property, ITS station units are designed for supporting secure provision of the C-ITS services and secure allocation of resources with prioritized access. Security means cover the two essential operational modes

  1. authentication of the sender of a broadcast message used for information dissemination, and
  2. secure session establishment and maintenance,

and station-internal controlled access to data and station functionalities, e.g. authentication (who is allowed to do what, or who is allowed to access which data and how <read / write / delete>?) and prioritization (who is served first?).

Due to the diverging requirements from the multiplicity of already known and continuously emerging ITS applications, multiple communication technologies that are fundamentally different can be supported in a specific ITS station unit. Supporting multiple access technologies and communication protocols, also referred to as “hybrid communications”, is a design principle of the ITS station architecture. The ITS station architecture is thus specified with no pre-defined mandatory communication technologies. It can support any type of existing and forthcoming technology to the conditions that

  1. it respects the same design principles;
  2. its integration into the ITS station architecture is specified in a support standard, and
  3. preserves backward compatibility with existing standards.

Presently, specifications have been developed to support a number of access technologies and several flavours of communication protocol suites.

The ITS station architecture actually combines

  1. localized communications, i.e. communications to nearby stations without involving networking from a source station through nodes of a network to a final destination station – also referred to as "ad-hoc communications" and
  2. networked communications.

Unlike many legacy applications, the choice of the access technology and communication protocol can be made transparent to the applications, i.e. ITS applications are technology-agnostic. This is achieved through a number of functionalities across the ITS station architecture in support of hybrid communications.

Before transmitting data, applications provide their communication requirements (level of priority, amount of data to be transmitted, expected level of security, expected end-to-end transmission delay, …) to the management entity of the ITS station unit for each type of communication flow. In the meantime, the management entity maintains various information (local regulation enforcing the use of a specific communication profile, existing capabilities of the ITS station unit and their status, characteristics and load of available radio technologies, current load of the ITS station unit, …). Based on the communication requirement and the current view of the management, the uppermost relevant communication profile is selected and ITS station resources are securely committed for identified communication flow.

Flexible and future-proof management of data and messages is a pre-requisite for success of C-ITS. New messages – even if efficiently defined in ASN.1 and encoded with Unaligned Packed Encoding Rules - can be made available during run-time of C-ITS simply by providing message configuration information. This allows for faster introduction of new or modified services and increases communications efficiency. An approach to achieve this is known under the title "Global Transport Data Management" (GTDM) framework with specifications provided in TS 21184.

Many C-ITS services depend on accurate information on the kinematics status, e.g. location and speed of a station at a given time, of the ITS station units. Thus, a general "Position-Velocity-Time" (PVT) service, as specified in TS 21176, is a pre-requisite for successful deployment of such services. The basic estimation technology used for the PVT service is the technology known under the name of "Global Navigation Satellite System" (GNSS), namely GALILEO from the European Union, GPS from the United States of America, GLONAS from the Russian Federation. However, in addition to this basic technology, a large variety of complementary technologies are known to improve accuracy and reliability of the PTV service.



This document specifies a generic position, velocity and time (PVT) service. It further specifies the PVT service within the ITS station (ITS-S) facilities layer (ISO 21217) and its interface to other functionalities in an ITS-S such as:

  • ITS-S application processes (ITS-S-APs), defined in ISO 21217;
  • the generic facilities service handler (FSH) functionality of the ITS station facilities layer, defined in ISO/TS 17429.

This document specifies:

  • PVT service which, dependent on a specific implementation, uses a variety of positioning-related sources such as global navigation satellite systems (GNSSs, e.g. GALILEO, GLONASS and GPS), roadside infrastructure, cellular infrastructure, kinematic state sensors, vision sensors;
  • a PVT service, which merges data from the above-mentioned positioning-related sources and provides the PVT output parameters (carrying the PVT information) including the associated quality (e.g. accuracy);
  • how the PVT service is integrated as an ITS-S capability of the ITS station facilities layer;
  • the interface function calls and responses (Service Access Point – service primitives) between the PVT ITS-S capability and other functionalities of the ITS station architecture;
  • optionally the PVT service as a capability of the ITS-S facilities layer; see ISO 24102-6;
  • an ASN.1 module C-itsPvt, providing ASN.1 type and value definitions (in Annex A);
  • an implementation conformance statement proforma (in Annex B), as a basis for assessment of conformity to this document.

NOTE It is outside the scope of this document to define the associated conformance evaluation test procedures.

This Technical Specification is published at CEN and at ISO. The electronic attachment to this Technical Specification, i.e. the machine-readable ASN.1 code, is freely available from ISO.



This document contains specifications for a set of ITS station security services required to ensure the authenticity of the source and integrity of information exchanged between trusted entities:

  • devices operated as bounded secured managed entities, i.e. "ITS Station Communication Units" (ITS-SCU) and "ITS station units" (ITS-SU) specified in ISO 21217, and
  • between ITS-SUs (composed of one or several ITS-SCUs) and external trusted entities such as sensor and control networks.

These services include authentication and secure session establishment which are required to exchange information in a trusted and secure manner.

These services are essential for many ITS applications and services including time-critical safety applications, automated driving, remote management of ITS stations (ISO 24102-2), and roadside/ infrastructure related services.

This Technical Specification is published at CEN and at ISO. The electronic attachment to this Technical Specification, i.e. the machine-readable ASN.1 code, is freely available from ISO in file1 and file 2..

There is a new work item at ISO and CEN with joint developement under the Vienna Agreement to upgrade TS 21177 to an EN SIO 21177, considering the improvements proposed by PT 1605.



This document specifies a global transport data management (GTDM) framework composed of

  • global transport basic data model,
  • global transport function monitor data model, and
  • global transport access control data model to support data exchange between applications and correct interpretation of data.

This document defines standardized data classes in a Global Transport Data Format (GTDF), and means to manage them.

Data exchange between ITS stations is based on messages and content composed of pre-configured information including conditional handling. Each message uses a global unique identifier and the associated data element. The format of the data element is specified by the global unique identifier pointing to configuration information including instructions for correct interpretation of the data element.

Application and role-based access control to GTDF resources are specified in conformance with IEEE 1609.2 certificates.

This document specifies GTDM as an ITS-S capability conformant with ISO 24102-6, which is an optional feature.

This Technical Specification is approved. Editorial comments are being resolved..


This document specifies a methodology to define ITS-S communication profiles (ITS-SCPs) based on standardized communication protocols to interconnect trusted devices. These profiles enable secure information exchange between such trusted devices, including secure low-latency information exchange, in different configurations. The present document, in order to exemplify the methodology, also normatively specifies some ITS-SCPs based on the methodology, yet without the intent of covering all possible cases. Further ITS-SCPs can be specified at a later stage.

Configurations of trusted devices for which this document defines ITS-SCP’s include:

  1. ITS station communication units (ITS-SCU) of the same ITS station unit (ITS-SU), i.e. station-internal communications;
  2. an ITS-SU and an external entity such as a sensor and control network (SCN), or a service in the Internet;
  3. ITS-SUs.

The specifications given in this document can be equally applied to secured and unsecured communications, being groupcast and unicast communications, being localized or networked communications.

This Technical Specification is approved and ready for publication..


TR 21186 is a multipart Technical Report. PT1605 developed 3 parts of it. Further parts are considered to be developed in the joint CEN/ISO C-ITS Working Group.

  • Part 1
  • Part 2
  • Part 3


This document describes standardization activities related to C-ITS on a global level by major standard development organizations (SDOs). It explains the various purposes of deliverables from SDOs and introduces a classification scheme of such documents. It presents an overview of standards with special relevance for C-ITS. It identifies an approach for C-ITS releases and exemplifies this approach.

This Technical Report is approved and ready for publication..


This document serves as a guideline explaining the concept of hybrid communications and support functionalities for Cooperative ITS services deployed in compliance with the ITS station architecture and related Cooperative ITS standards.

This Technical Report is approved and ready for publication.


This document provides guidelines on security applicable in Intelligent Transport Systems (ITS) related to communications and data access.

Especially, analysis and best practice content is provided in this document for secure ITS connectivity using ISO/TS 21177.

This document analyses and recommends application security, access control, device security and public key infrastructure requirements for a secure ITS ecosystem.

This Technical Report is in the final ballot process until 31.12.2020.



  1. An introduction in the work of PT1605 is presented in the first newsletter from PT1605.
  2. Invitation for the first webinar on 21. April 2020.
  3. The first edition of the C-ITS Brochure is released by CEN/TC 278.


PT1605PT1605 will prepare for several webinars. You may register for attending a webinar by sending an email, providing your name, your affiliation, country of residence, and the date of the respective webinar. Upon registration, you will receive an email with the login information.

Note on data privacy: By sending the registration request to us, you authorize us to store temporarily and use the contained personal information in a way needed to support you in attending the webinar. Your personal information will not be used for other purposes, and will be deleted as soon as the webinar activities are finished.

  • Further webinars
  • 12. January 2021
  • 10. December 2020
  • 19. November 2020
  • 8. September 2020
  • 24. July 2020
  • 18. June 2020
  • 21. April 2020
... in preparation

PT 1605 is engaged in a series of webinars organized by SAMS Norway and ITS Norway.

The first webinar in this sequence will be on 12. January 2021 with the title "ITS Standards: Key enabling technologies". Please register for the event.

Hybrid Communications - How to use the standards

PT1605 arranged for a webinar on technologies that are, beyond other purposes, supporting "Hybrid Communications".

See the invitation.

The presentations:

The webinar movie.

The role of "Secure Vehicle Interface" standards in ITS

PT1605 arranged for a webinar on technologies that are, beyond other use domains, applicable for the "Secure Vehicle Interface" (SVI).

See the invitation.


The SVI is an instantiation of a "Secure Network Interface" (SNI). SNIs are given in several implementation contexts, e.g. in a vehicle, at the roadside, in central stations, and even in portable devices (see also the implementation contexts of ITS station units illustrated in ISO 21217). Although the SVI is the most popular SNI today, the presentation aims on explaining the global usage of TS 21184, and gives examples also for a sensor and control network installed at the roadside.

The presentations:

On 8. September 2020, an online demo of the PT1605 technologies in support of the SVI was organized.

SVI demo

The webinar is now available as video.

Ahead of this event, a group of leading mobility players has endorsed this technology as an optimal solution to enable innovation, competition and consumer protection in this space. More details on this group of supporters is published..ESF GmbH is supporting this approach.

On 24. July 2020, PT1605 contributed to a webinar organized by DG GROW, presenting the PT1605 deliverables that are relevant for the "Secure Vehicle Interface" (SVI).

On 18. June 2020, PT1605 contributed to a webinar organized by the Standards Insitute of Israel (SII). This webinar is on C-ITS technologies that are not just ready for deployment, but that are, after successful validation, already deployed. The contribution from PT1605 will be on technical features in support of "day-2+" applications.

The agenda for download.

The presentations for download:




The first webinar will be on 21. April 2020 from 13:00h through 17:00h Central Euorpean time (UTC+2).

The presentations for download:

Please present your interest in subsequent webinars by email, telling us your preferred technical topics.




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