(Continuation of Q.11, Q.12, Q.13 and Q.15/17)
This Question covers formal languages to define the requirements,
architecture, and behavior of telecommunications systems: requirements
languages, specification and implementation languages and languages for Open
Distributed Processing (ODP). The formal languages for these areas of
engineering are widely used in industry and ITU-T and commercial tools support
It has become increasingly important to address Unified Modelling Language (UML)
in combination with the ITU-T languages. UML 2.0 has adopted some of the
elements of the ITU-T Languages and provides a framework to specialize modelling
languages to a particular domain through profiling and also to integrate
notations. ITU-T languages can be integrated by means of UML profiles. Z.119
provides guidelines for writing such profiles, and Z.109 is such a profile for
the Specification and Description Language.
For harmonization, the languages need to be compared with each other. The
meta-grammars of the languages differ, which means that a reader of the
Recommendations for different languages has to learn different meta-grammars and
the UML profiles may also differ. The harmonizing of the grammar used in the
languages is thus a further objective of this Question.
Formal languages can also be used for writing high quality Recommendations.
Guidelines for doing so are given in Z.450; further advice on the application of
the languages can be found in Z.110. The methodology documents are given in
Z.100 Supplement 1, which addresses methods and principles used in a particular
The Recommendations in the Z.10x-series concern the Specification and
Description Language. These Recommendations need to be maintained to meet the
needs of users in ITU and industry, and to the development of languages
elsewhere, such as at the Object Management Group (OMG). Systems have been
engineered using the programming language CHILL (Z.200) so this should be
retained as is, though CHILL is no longer considered appropriate for further
Relevant Requirements languages that fulfil an important role in the early
state of analysis to capture user requirements are Message Sequence Chart
(Z.120), and the User Requirements Notation (URN) - Language requirements and
framework (Z.150). The URN goal-oriented requirements language and use case maps
(UCM) are given in Z.151.
A key aspect of telecommunications systems development is the availability of
software to support Open Distributed Processing (ODP). Provision of ODP requires
standardization of reference models, architectures, functions, interfaces and
languages for specifying these (X.900-series).
Recommendations and Supplements under responsibility of this Question as of 1
December 2008: X.901, X.902, X.903, X.904, X.906, X.910, X.911, X.920, X.930,
X.931, X.950, X.952, X.960, Z.100, Z.104, Z.105, Z.106, Z.109, Z.110, Z.111,
Z.119, Z.120, Z.121, Z.150, Z.151, Z.200, Z.400, Z.450, Z.600, Z.601 and
Supplement 1 to the Z-series.
Study items to be considered include, but are not limited to, what new
Recommendations, changes to existing Recommendations, or other provisions are
- Ensure the releases of the languages are adapted to further contemporary
- Support the use of the languages in emerging new architectures and
- Establish a coherent set of languages supporting development from
requirements and high-level design to implementation, execution and deployment?
- Support of new versions of related languages such as Abstract Syntax Notation
One (ASN.1) and Interface Definition Language (IDL)?
- Support the computational modelling of a new generation of telecommunications
- Allow the use of ISO/IEC 10646 text to aid human understanding in
annotations, names and identifiers, and in text handled in the languages?
- Define or revise the definitions of new or existing languages, methodologies
- Enable an improved use of UML and ITU-T languages, focusing on improving
productivity and the ability to ensure quality?
- Determine which additional models, architectures, functions, interfaces and
languages are necessary to extend and complement the Reference Model ODP (RM-ODP)
for the construction of secure, real-time, and dependable open distributed
- What support is needed for the formal languages to play a role in the sensing
and alerting of events caused by climate change?
Tasks include, but are not limited to:
- Maintain a master list of corrections of the current versions of all
languages under maintenance.
- Maintain the formal basis for Recommendations, thereby placing emphasis on
ease of use and easy maintainability, and continue to maintain the formal basis.
- Maintenance of Z.10x-series, Z.11x-series, Z.12x-series, Z.15x-series, Z.400,
Z.450, Z.600-series and X.900-series Recommendations as and when needed. The
direction of the effort should be towards relative stability of the languages
but with improved usability.
- Contribute to the development of UML 2.0 profiles for: Abstract Syntax
Notation One (ASN.1), Message Sequence Chart (MSC), Testing and Test Control
Notation (TTCN), User Requirements Notation (URN), and other ITU-T languages.
- Identify and if needed adopt other relevant requirements, specification and
implementation languages as ITU-T Recommendations taking into account Z.110.
- Produce a Supplement to the Z-series Recommendations provisionally entitled
"Methodology on the use of description techniques" to replace Z.100 Supplement 1
(10/96) and include a tutorial on the use of UML with ITU-T languages.
- Revision of RM-ODP Recommendations in collaboration with ISO/IEC JTC 1/SC 7/WG
- Consider the use of ISO/IEC 10646 text in all areas of the languages with the
possible exception of keywords.
Recommendations: X.68x- and X.69x-series
Questions: ITU-T Qs 12 and 14/17
Study groups: ITU-T study groups that use ITU-T languages, including SGs 2,
11, 13 and 16
Standardization bodies: ISO/IEC JTC 1; ISO/IEC JTC 1/SC 7/WG 19; ETSI; OMG;
Other bodies: SDL Forum Society