International Telecommunication Union © ITU-T Study Group 17 Use of ITU-T Formal Languages Amardeo Sarma NEC Europe Ltd.

2 © ITU-T Study Group Current status of use of ITU-T formal languages o ETSI comprehensively and successfully used ASN.1, SDL, MSC and TTCN High-level MSC popular TTCN-2 TTCN-3 o IETF Some impact of SDL in IETF already in the OSPF area and through special IETF sessions EU Project Daidalos plans to model protocols with UML/SDL/MSC and contribute to IETF o Nokia has successfully used ITU-T languages Protocol emulators useful to check change requests Lot of ASN.1 use TTCN-2 TTCN-3

3 © ITU-T Study Group Observation on the state of things today o UML use is growing everywhere and has become a marketing factor o Tool vendors use UML with SDL/MSC, SDL/MSC are sometimes hidden o Not only the actual work to be done at ITU-T, their marketing becomes increasingly important Should SDL, TTCN and MSC be separately marketed or as part of UML o Discussion on simplification of SDL remains controversial Integration with testing or not? Clarify how to simplify languages

4 © ITU-T Study Group Differentiating factors: still relevant? o Real-time, distributed communicating systems o Formal, allowing verification and validation o Many languages with a graphical syntax o Commercial tool support o Catering for users both in Industry and in Standards bodies (SDOs), e.g. ITU-T SG 11 These have been our differentiating factors and strengths

5 © ITU-T Study Group From previous presentation: Co-Evolution of Techniques o SDL/MSC and UML have co-evolved o Full UML 2.0 recognition planned by ITU-T o SDL graphical presentation syntax for UML is an option o A UML profile should be an ITU-T Recommendation and OMG Standard o Arrangement with OMG such as joint meetings to promote co-evolution and save meeting time.

6 © ITU-T Study Group From previous presentation: Language development goals o Controlled simplification of ASN.1, SDL, MSC and TTCN o Abstract (more convenient) view for standards developers w.r.t. ASN.1, SDL o Combine ASN.1, SDL, MSC and TTCN via UML Ensure co-ordinated development Applies to eODL and URN as well o Provide professional support and more (free) tools

7 © ITU-T Study Group A proposal: The future of ITU-T formal languages o Co-Evolution of UML and ITU-T languages remains important o UML Profiles are on the agenda o Involve input from the VeUML work o Simplification is on the agenda o Free tools are required, UML profile will help! o Use of ITU-T Languages IETF is an important if not essential body for input using ITU-T languages NGN needs formal languages this is an opportunity