1 / 21

ITU-T Languages @ SDOs

ITU-T Languages @ SDOs. Amardeo Sarma Co-Chairman, ITU-T Study Group 17. Goal of standardisations. Create a common understanding for and define Infrastructure Products Services Protocols Enable Communication Enable interoperability and compatibility Ease the life of providers and users.

wilma-mcmahon
Download Presentation

ITU-T Languages @ SDOs

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ITU-T Languages @ SDOs Amardeo SarmaCo-Chairman, ITU-T Study Group 17

  2. Goal of standardisations • Create a common understanding for and define • Infrastructure • Products • Services • Protocols • Enable Communication • Enable interoperability and compatibility • Ease the life of providers and users ITU-T Study Group 17

  3. Special Core Competencies at ITU-T • Carrier class standards and specifications • Experts and drivers in Telecommunications • Strong organisational and logistic support by the TSB • Fast standards track • make even better standards faster Quality of standards play a key role ITU-T Study Group 17

  4. Writing standards • Natural languages • Tables • Diagrams, e.g. sequence diagrams • State diagrams • ...... Usually informal – meaning unclear ITU-T Study Group 17

  5. Improve standards clarity • Natural languages and informal aids not enough • Use formalised techniques • Meaning (semantics) of used notation • Allow automatic checking • Machine-readable specifications – automatic implementation • Since the 70s, ITU-T (then CCITT) has developed FDTs – formal description techniques • Today: ITU-T Language Family ITU-T Study Group 17

  6. What makes the family different? • Real-time, distributed communicating systems • Formal, allowing verification and validation • Supports transparency and security requirements • Many languages with a graphical syntax • Commercial tool support • Tool availability required for approval • Tools vendors directly involved in work • Catering for users both in Industry and in Standards bodies (SDOs), e.g. ITU-T SG 11 ITU-T Study Group 17

  7. The ITU-T language family • SDL – Specification and Description Language • MSC – Message Sequence Chart • eODL – extended Object Definition Language • ASN.1 – Abstract Syntax Notation One • TTCN – Tree and Tabular Combined Notation • CHILL – CCITT HIgh-Level Language • URN – User Requirements Notation • Incorporating Time and Performance into the languages ITU-T Study Group 17

  8. Language Usage • Initially, languages were mainly aimed at standards and Recommendations • For the core languages, industrial use has today far outgrown use in standards! • There is considerable potential left for SDOs to: • Improve quality of standards • Reduce time for standards development • But: Use requires some investment ITU-T Study Group 17

  9. Our Strategy at ITU-T SG 17 Keep the edgeby concentrating on thedifferentiating factors and focusing on our strengths ITU-T Study Group 17

  10. What about UML? • UML is generic, SDL/MSC/TTCN are specific • SDL and MSC experts key for UML 2.0 • Tools for joint support available • UML without SDL is like a car without an engine • Co-operation with OMG in progress • If you really want UML, you can use it without losing the benefits of SDL/MSC ITU-T Study Group 17

  11. What about XML? • ASN.1 + XCN (XML Control Notation) • as powerful and expressive asXSD (XML Schema Definition) • less verbose and much more readable. • ASN.1 is a mature schema notation for XML. No schema mapping is needed • ASN.1/XER: efficient binary encodings with XML (+ XSL)display (or transfer if needed) • CXER èASN.1/XER as a canonical variant of XER for secured transactions • XER tools : http://asn1.elibel.tm.fr/links/#xml ITU-T Study Group 17

  12. UML and XMLare easy and popular ASN.1, MSC, SDL and TTCNsupport secure, hi-quality standards You use the best of two worlds ITU-T Study Group 17

  13. What ITU-Languages do for you • Provide a method supported by tools • Free ASN.1 tools • Free Telelogic reader • Allow checking correctness on the fly • Is the behaviour is what you really intended? • Improves the quality of the standard • Interoperability is greatly improved • Once used properly, helps save time! ITU-T Study Group 17

  14. Obstacles to Language Use • Benefit unclear • Check track record • Formality reduces freedom • Freedom only reduced for issues needed for interoperation, use correct dose of formality • Quick and dirty is better • Are you going to spend more time later fixing holes? ITU-T Study Group 17

  15. Obstacles to Language Use • No expertise in group • Specialists should concentrate on their domain – get support for languages • Missing support • ITU TSB should provide this! • Or ask SG17 – we could e.g. provide tutorials in SDL, ASN.1 etc. • In general: Expertise is available ITU-T Study Group 17

  16. Examples of successful use • ASN.1 • Intelligent network • GSM • UMTS (3G cellphones) • Voice over IP • SDL • IN CS-2 / CS-3 • OSPF (IETF) ITU-T Study Group 17

  17. Remaining problems • Viewing different levels of abstraction • Simplify techniques – lost intuitiveness • Bridge the gap to users without specialist knowledge of formal techniques • Enable bottom-up ITU-T Study Group 17

  18. Tool usage at ITU-T • SDT is currently the standard tool at ITU and ETSI • Recommendation authors send SDT files, which are checked by TSB staff • Formal descriptions are considered non-copyrighted • Common Interchange Format CIF is very important (e.g. for those using Cinderella)! • Availability of cheap or free lightweight tool for standards greatly helps promote SDL/MSC • The ITU-T CD-ROM, also available for you all, has been a step in this direction! ITU-T Study Group 17

  19. Professional support is needed! • To further improve standards quality, SG17 reinforced the recommendation that TSB provide • expertise on a regular basis in the ITU-T languages and methodologies concerning the use of the languages • tools, supporting and facilitating the use of ITU-T languages • We really need permanently available experts at ITU-T: • ETSI success story • Demand must come from users ITU-T Study Group 17

  20. Summary of possible actions • Understand level of quality and need for formalised techniques • Make tool support available • Make professional support available • Tools need improvement to cater for users developing standards • Enable constant feedback from users in standards as from industry • Use the crisis – Start a case study with Q16/11? ITU-T Study Group 17

  21. Plenty of information on the web ITU-T SG17:http://www.itu.int/ITU-T/studygroups/com17/index.htmlASN.1 Consortium: http://www.asn1.orgSDL Forum Society: http//www.sdl-forum.orgIndian SDL and TTCN Forum: http://www.sdl-ttcnforum.org/

More Related