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ETSI MTS Meeting: 3GPP and SDL. Oct-2000. Telelogic's Position. Telelogic actively collaborates with the standardization bodies Contributors can obtain Telelogic UML, SDL and TTCN tools through ETSI All the Suites are both available on Windows and Unix
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ETSI MTS Meeting: 3GPP and SDL Oct-2000
Telelogic's Position • Telelogic actively collaborates with the standardization bodies • Contributors can obtain Telelogic UML, SDL and TTCN tools through ETSI • All the Suites are both available on Windows and Unix • A team led by Olle Hydbom is involved in 3G standardization work (and GSM) • Has directly supplied 3G contributors with some Tau licenses • Is providing expertise (for free) in order to make specifications processable by tools, e.g. Call control, etc. • There were some regressions with GSM specifications reused in the UMTS context
Current Use of Modeling Techniques for UMTS Specifications Status by June-00 • Total number of specification documents = 238 • SDL = 32 • ASN.1 = 12 • MSC = 28 • UML Class diagram = 3 • TTCN = 3 • Sequence charts = 51 • State diagrams = 22 • Quality of the diagrams • Not necessarily formal and coherent • Mainly for informative description • Not clear if the SDL specifications are normative or informative
Analysis of the Use of UML • UML is considered as not formal enough to provide valuable help in protocol specifications and has not been discussed in the RAN#2 methodology group at all. • Consequence: infrequent use
Analysis of the Use of SDL/MSC • SDL is more used in UMTS than in GSM, but not enough • Much of the SDL comes from GSM • Too few new uses • An example of new use: Radio Link Control layer (RLC) • 80 pages • Informative • Time and SDL expertise were missing on the industrial contributor's side • Contributors: NTT Cocomo and Telelogic, Nokia as reviewers • Positive results in the use of SDL: Errors have been found by simulation • Conclusion: Limited dissemination of SDL
Potential Benefits of Using SDL/MSC • UMTS is considerably more complex than GSM • This can lead to poor quality in the protocol specifications and be behind the delivery schedule • SDL is needed for • Better specification • Unambiguous • Detection of inconsistencies • Detection of errors by simulation • Easier production of conformance test cases • Production of TTCN test cases by simulating models
Analysis of the Use of SDL/MSC • Causes • Reluctance of some customers to use SDL • Because they do not use SDL later in their development process • SDL is not sufficiently well-known by 3GPP contributors • And is considered as difficult to understand
Proposal • Our feeling is that 3G contributors (telecom equipment manufacturers) are ready to use SDL, but they are not educated enough • To have more SDL in UMTS, ETSI should supply training classes • A concrete example: STF 160/161 is developing conformance test suites in TTCN (MAC, RLC and RRC layers…) • They hoped to start from formal SDL • They cannot use tools today due to lack of formal SDL • Consequence: be behind the time schedule