1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T Series Z TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Supplement 1 (04/2015) SERIES Z: LANGUAGES AND GENERAL SOFTWARE ASPECTS FOR TELECOMMUNICATION SYSTEMS ITU-T Z.100-series SDL+ methodology: Use of ITU System Design La
2、nguages ITU-T Z-series Recommendations Supplement 1 ITU-T Z-SERIES RECOMMENDATIONS LANGUAGES AND GENERAL SOFTWARE ASPECTS FOR TELECOMMUNICATION SYSTEMS FORMAL DESCRIPTION TECHNIQUES (FDT) Specification and Description Language (SDL) Z.100Z.109 Application of formal description techniques Z.110Z.119
3、Message Sequence Chart (MSC) Z.120Z.129 User Requirements Notation (URN) Z.150Z.159 Testing and Test Control Notation (TTCN) Z.160Z.179 PROGRAMMING LANGUAGES CHILL: The ITU-T high level language Z.200Z.209 MAN-MACHINE LANGUAGE General principles Z.300Z.309 Basic syntax and dialogue procedures Z.310Z
4、.319 Extended MML for visual display terminals Z.320Z.329 Specification of the man-machine interface Z.330Z.349 Data-oriented human-machine interfaces Z.350Z.359 Human-machine interfaces for the management of telecommunications networks Z.360Z.379 QUALITY Quality of telecommunication software Z.400Z
5、.409 Quality aspects of protocol-related Recommendations Z.450Z.459 METHODS Methods for validation and testing Z.500Z.519 MIDDLEWARE Processing environment architectures Z.600Z.609 For further details, please refer to the list of ITU-T Recommendations. Z series Supplement 1 (04/2015) i Supplement 1
6、to ITU-T Z-series Recommendations ITU-T Z.100-series SDL+ methodology: Use of ITU System Design Languages Summary This Supplement is published as a Supplement to the ITU-T Z.100 Series for ITU System Design Languages (that is, Recommendations ITU-T Z.100 to Z.107, Z.109, Z.110, Z.120, Z.121, Z.150,
7、Z.151 and Z.160 to Z.170). This Supplement 1 to the ITU-T Z.100 series of Recommendations outlines a methodology (called SDL+) for the use of these languages in combination, in particular where the ITU Specification and Description Language is used. This Supplement covers the following topics: 1) te
8、rminology definitions and background material on the use and application of the ITU Specification and Description Language and related ITU System Design Languages; 2) an overview of the methodology (clause 4); 3) more detailed descriptions of: a) analysis of the requirements (clause 5) b) draft desi
9、gn and investigation of the application (clause 6) c) formalization of the application into a model of how an application behaves (clause 7) d) implementation issues (clause 8) e) validation (clause 9). 4) relationship with other languages and techniques; 5) an elaboration of the methodology for ser
10、vice specification. This Supplement is not exhaustive. The intention is that users of SDL+ incorporate it in their overall methodologies, and tailor it for their application systems and specific needs. In particular, this Supplement does not cover the issues of derivation of an implementation from t
11、he specification, or the testing of systems in detail. In the case of testing, it is expected that this will be covered by a methodology dealing with the generation of tests for standards or products based on SDL+. The methodology is a framework to be elaborated for the context of actual use. This S
12、upplement has two parts. In Part I the framework is explained as an overview in clause 4, and with a more detailed description of the main parts in clauses 5, 6 and 7. The general framework is then specialized for the case of services specification in Part II, starting at clause 12. The parts from c
13、lauses 5, 6 and 7 are elaborated in clauses 13, 14 and 15. In this specialization some choices of approach have been made. Many of the details given in clauses 13, 14 and 15 can be used when the general framework is elaborated for other contexts and other choices. History Edition Recommendation Appr
14、oval Study Group Unique ID* 1.0 ITU-T Z Suppl. 1 1997-05-06 10 11.1002/1000/4297 2.0 ITU-T Z Suppl. 1 2015-04-17 17 11.1002/1000/12447 _ * To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommendations unique ID. For example
15、, http:/handle.itu.int/11.1002/1000/ 11830-en. ii Z series Supplement 1 (04/2015) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standar
16、dization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), whic
17、h meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within IT
18、U-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this publication, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this publication is v
19、oluntary. However, the publication may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the publication is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the
20、negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the publication is required of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this publication may involve the use
21、of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the publication development process. As of the date of approval of this publication, ITU ha
22、d not received notice of intellectual property, protected by patents, which may be required to implement this publication. However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/I
23、TU-T/ipr/. ITU 2015 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Z series Supplement 1 (04/2015) iii Table of Contents Page 1 Context 1 2 Definitions 1 3 The advantage of using SDL+ 4 3.1 Understanding an SD
24、L+ specification 5 3.2 The application area of SDL+ 6 3.3 Relation to implementation 6 PART I THE FRAMEWORK METHODOLOGY 8 4 Overview of activities and an outline of the methodology . 8 4.1 The Requirements Collection part of requirements capture . 12 4.2 Analysis, Draft Design and Formalization . 13
25、 4.3 Validation and Testing . 14 4.4 Documentation . 15 4.5 Parallelism of activities 16 5 Analysis activity . 16 5.1 Starting Analysis 17 5.2 Questions during Analysis 18 5.3 Modelling approach for Analysis . 18 5.4 Analysis steps . 18 5.5 Conclusion of Analysis . 19 6 Draft Design 20 6.1 Starting
26、Draft Design 21 6.2 Draft Design steps 22 6.3 Conclusion of Draft Design 23 7 Formalization 23 7.1 Starting Formalization 24 7.2 Formalization steps . 24 7.3 Conclusion of Formalization 25 8 Implementation . 25 9 Validation . 27 9.1 Characteristics of a validation model . 28 9.2 Comparison of the va
27、lidation model with the formalized model . 28 9.3 Issues in defining the validation of a specification 29 10 Relationship with other methodologies and models . 29 10.1 Relationship with Recommendations I.130/Q.65 (3-stage method) 1988 . 29 10.2 Relationship with OSI layered modelling 31 10.3 Relatio
28、nship with ITU-T Q.1200-series (IN) architecture and SIBs 46 10.4 Relationship with remote operations (RO and ROSE) in b-ITU-T X.219 46 11 Justification of approach . 47 iv Z series Supplement 1 (04/2015) Page PART II AN ELABORATION OF THE FRAMEWORK METHODOLOGY 48 12 Elaboration of the methodology f
29、or service specification 48 12.1 Three-stage methodology: Stage 2 (Recommendation ITU-T Q.65) . 48 13 Analysis steps . 52 13.1 Inspection step 53 13.2 Classification step for object modelling . 53 13.3 Classification step for use sequence modelling 58 14 Draft Design steps . 61 14.1 Component relati
30、onship modelling 62 14.2 Data and control flow modelling 63 14.3 Information structure modelling . 64 14.4 Use sequence modelling . 66 14.5 Process behaviour modelling 68 14.6 Overview modelling . 68 15 Formalization steps . 72 15.1 Structure steps (S-steps) . 73 15.2 Behaviour steps (B-steps) . 82
31、15.3 Data steps (D-steps) 87 15.4 Type steps (T-steps) . 93 15.5 Localization steps (L-steps) 98 Bibliography. 102 Z series Supplement 1 (04/2015) 1 Supplement 1 to ITU-T Z-series Recommendations ITU-T Z.100-series SDL+ methodology: Use of ITU System Design Languages 1 Context This Supplement is int
32、ended for those persons responsible for methodology in areas where the Recommendation ITU-T Z.100-series are used. The objective of this Supplement is to provide a methodology for the effective use of the ITU-T Z.100-series Language Recommendations: the Specification and Description Language (SDL-20
33、10) b-ITU-T Z.100, b-ITU-T Z.101, b-ITU-T Z.102, b-ITU-T Z.103, b-ITU-T Z.104, b-ITU-T Z.105, b-ITU-T Z.106, b-ITU-T Z.107; and the Message Sequence Chart notation b-ITU-T Z.120. The application of this methodology should lead to a well-defined specification of the target application in SDL-2010 com
34、bined optionally with ASN.1 b-ITU-T X.680, b-ITU-T X.681, b-ITU-T X.682 and b-ITU-T X.683 and Message Sequence Chart notation b-ITU-T Z.120. When b-ITU-T Z.105 is used, SDL-2010 is used to define behaviour and ASN.1 is used to define data. It is also possible to use SDL-2010 to define data as in b-I
35、TU-T Z.104. This Supplement covers the use of SDL-2010 without ASN.1 as well as combined with ASN.1 as in b-ITU-T Z.105. Message Sequence Chart diagrams are used to describe sequences of events and normally do not cover every possibility. Message Sequence Chart diagrams are used to describe what hap
36、pens for particular sequences of stimuli, whereas SDL-2010 defines how an application system behaves towards all stimuli for every possible status. Message Sequence Chart diagrams without SDL-2010 would not usually give a full description of system behaviour. In the methodology described in this Sup
37、plement, SDL-2010 would not normally be used without Message Sequence Chart diagrams. The Supplement does not describe a general methodology for the use of the Message Sequence Chart notation either alone or with languages other than SDL-2010 (with or without ASN.1). Since the methodology assumes th
38、e use of SDL-2010 with ASN.1 and Message Sequence Chart notation, the term “SDL+“ is used throughout the Supplement to mean “SDL-2010 with ASN.1 and Message Sequence Chart notation“. It is recognized that there are many ways of using SDL+, depending on the users preference, on the target application
39、, on the in-house rules of the organization, etc. The methodology in this Supplement is therefore incomplete and will need to be elaborated to produce the actual methodology for a particular context. This Supplement is to provide assistance to users of SDL+ and to promote unified usage and tool supp
40、ort of the language. 2 Definitions This Supplement defines the following terms: 2.1 activity: A specific procedure in an engineering process, supported by one or several methods. 2.2 agent: An object that models how an entity behaves in the environment and application system. 2.3 actor: A person (or
41、 organization) in the environment of a system that has one or more roles of interaction with a system. In the context of this Supplement, an actor that interacts with the activities in the engineering system is called an engineer. 2 Z series Supplement 1 (04/2015) 2.4 analysis: The stepwise activity
42、 for exploring collected requirements, organizing the information they contain, and recording this information in a format that reflects this organization (see clause 5). 2.5 application concept: A concept pertaining to a given application domain and the system that is being specified. 2.6 applicati
43、on domain: The field of activity in which the application system under specification will operate. 2.7 application system: (abbreviated to system where the qualifying term can be derived from context) the complex set (of parts) that is used to provide functionality and other characteristics. In the
44、context of this Supplement there is usually no distinction between a system specification, a system description and a real system instance. 2.8 ASN.1: Abstract Syntax Notation One b-ITU-T X.680, b-ITU-T X.681, b-ITU-T X.682 and b-ITU-T X.683. 2.9 association: A dependency relationship between two or
45、 more classes (or two or more objects) in the Unified Modeling Language (see clause 13.2 and b-OMG UML), and shown as an annotated line between class (or object) symbols. 2.10 behaviour: Sequence of actions with stimulus and response aspects performed by a system that may change its state. 2.11 clas
46、s: A description of the model of the system defining a set of objects that have similar properties (same structure and same behaviour). A class represents an application concept. 2.12 classified information: A model with the collected requirements structured and defined according to concepts that ha
47、ve been named and defined. 2.13 collected requirements: A set of requirements for the application collected as a result of the requirements collection activity. 2.14 computational view: A view of a system and its environment that focuses on decomposition of the system to allow for distribution (see
48、“computational“ viewpoint in b-ITU-T X.903, clause 4.1). 2.15 design view: A view of a system and its environment that focuses on the functions required to support that system (see “engineering“ viewpoint in in b-ITU-T X.903, clause 4.1). 2.16 draft design: The stepwise activity for engineering part
49、ial or partly informal specifications from different points of view and at different levels of detail to investigate engineering design choices (see clause 6). 2.17 draft designs: Outline designs for the system under consideration using one or more models that describe the system partially. 2.18 documentation: The activity for selecting, cataloguing and storing the information about a product. 2.19 enterprise view: A view of a system and its enviro