As the primary objective of this handbook is the harmonisation of the ITS service deployment throughout Europe, the “harmonisation and advice concept” is the very core of the handbook. Here, for each of the European ITS Core Services, requirements and advice are formulated from a pan-European perspective in such a way that
It is essential for every prescriptive document to provide specifications in a well-defined and unambiguous language. There are various definitions that clarify the use of particular words (such as those listed below) within their prescriptive texts.
For the purpose of this ITS Reference Handbook, the well-established provisions of the RFC 2119 are used, which is used to specify the basic Internet standards:
The ITS service key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “MAY” and “OPTIONAL” in this document are to be interpreted as described in RFC 2119. An overview of the keywords, their meaning and the possible answers in the context chapter Harmonization requirements and advice is provided in Table 6.
Table 6: Requirement wording
In general, the keywords in brackets are possible, but their use is not recommended in order to avoid confusion which may arise because of different common linguistic usage of the terms in the different EU member states.
Note: the capitalisation of these keywords that is frequently used in Internet standards is not recommended for the ITS Deployment Reference Handbook.
The use of this “requirements language” allows the direct transfer of the requirements stated in chapter Harmonization requirements and advice to a compliance checklist.
Against this background, the manual provides a formal ITS service definition and requirements and advice in a total of 6 chapters:
Common Look & Feel requirements
Required standards and specifications
Level of Service Definition