1、ITU-T RECMN*Z=352 93 m 4862.593 0584319 171 m INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU MAN-MACHINE LANGUAGE 2.352 (03/93) DATA ORIENTED HUMAN-MACHINE INTERFACE SPECIFICATION TECHNIQUE - SCOPE, APPROACH AND REFERENCE MODEL ITU-T Recommendation 2.352
2、(Previously “CCITT Recommendation”) ITU-T RECMNaZ.352 93 4862591 0584320 993 W FOREWORD The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the International Telecom- Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World
3、Telecommunication Standardization Conference (WTSC), which meets every four years, established the topics for study by the ITU-T Study Groups which, in their turn, produce Recommendations on these topics. ITU-T Recommendation 2.352 was prepared by the ITU-T Study Group I (1988-1993) and was approved
4、 by the WTSC (Helsinki, March 1-12, 1993). munication Union. The ITU-T is responsible for studying technical, operating and tariff questions and issuing I 1 NOTES 1 As a consequence of a reform process within the International Telecommunication Union (ITU), the CCITT ceased to exist as of 28 Februar
5、y 1993. In its place, the ITU Telecommunication Standardization Sector (ITU-T) was created as of 1 March 1993. Similarly, in this reform process, the CCIR and the IFRB have been replaced by the Radiocommunication Sector. In order not to delay publication of this Recommendation, no change has been ma
6、de in the text to references containing the acronyms “CCITT, CCIR or IFRB” or their associated entities such as Plenary Assembly, Secretariat, etc. Future editions of this Recommendation will contain the proper terminology related to the new ITU structure. 2 telecommunication administration and a re
7、cognized operating agency. In this Recommendation, the expression “Administration” is used for conciseness to indicate both a O ITU 1994 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and mi
8、crofilm, without permission in writing from the ITU. ITU-T RECMN*Z=352 93 4862591 O584321 82T = CONTENTS 1 Scope of specification technique 3 2 Approach 2.1 Data versus functions 2.2 Consequences . 2.3 Data design . Reference model . 3.1 Overview 3.2 Scope 3.3 Subdivision of the external layer Annex
9、 A - Guidelines for KMI developers . A.l Introduction A.2 Method A.3 Data design . Appendix I - Additional guidelines for data designs . 1.1 General 1.2 Design of classes . 1.3 Design of identifiers . 1.4 Derived data and level of detail Page 1 1 1 1 3 3 3 4 6 6 6 7 10 12 12 12 16 21 Recommendation
10、2.352 (03/93) 1 ITU-T RECMN*Z.352 93 = 4862593 0584322 766 m SUMMARY This Recommendation provides a framework for specifying harmonized HMIs. The Recommendation points out the importance of identifying the right application area and the great impact this choice will have on the final design of the H
11、MI. Therefore, a data oriented approach, rather than a functional approach, is proposed. A three-layered reference model for HMI is introduced and explained. This reference model allows the centralization of data definitions for HMI and derivation of external presentations in a harmonized manner. An
12、nex A provides guidelines for how to carry out development of HMIs in accordance with the chosen reference model and formalism. The development method is not a waterfall-type development process. This annex also provides a framework for design of data seen at the HMI. Appendix I provides additional
13、guidelines for data design. The mapping between the HMI reference model and the TMN functional architecture is under study. Areas that this Recommendation has relations with and impact on, include: - mapping to TMN specifications, - software standardization. 11 ITU-T RECMN*Z*352 93 48b2571 0584323 b
14、T2 Recommendation 2.352 DATA ORIENTED HUMAN-MACHINE INTERFACE SPECIFICATION TECHNIQUE - SCOPE, APPROACH AND REFERENCE MODEL (Helsinki, 1993) 1 Scope of specification technique The objective of this specification technique is to specify the data seen at the HMI and the grammar for these data. It is n
15、ot the objective to define how the telecommunication networks operate internally. The specification of the data is used by the end users prior to the implementation: - - - - to assess what an application is about; to ensure that its grammar is correctly understood; to ensure that its terminology is
16、well chosen; and as a central part of a contract for the implementations. The specifications should also be applicable as a means for: - - user guidance to the permissible and/or mandatory structure of the data and the explanations of the data; accessing the “instances” of the data for that applicat
17、ion. From this it follows that the specifications should be readable by and applicable to both designers and end users. The designers can be both HMI designers and software designers. The end users can be both OA while the data oriented approaches provide more flexibility for changes in the sequence
18、s of tasks. Both training and usage of systems designed according to the two different approaches tend to be very different. In the function oriented designs the users learn and use the different functions of the system and learn only implicitly about the universe of discourse, i.e. application area
19、, and the structure of the data being manipulated by the functions. In the data oriented approaches the emphasis is put on understanding the application area being administered by the system and defined by the structure of the data of the system; the training on tasks to be performed is given less p
20、riority. 2 Recommendation 2.352 (03/93) ITU-T RECflNaZ.352 93 = 4862.591 0584325 475 While function analysis can help to identify needs for data, function analysis does not help to identify data for additional functions, for new users or to identify unrelated data. Therefore, function analysis can c
21、onstrain rather than support innovation and the questioning of existing data definitions. While the decomposition of functions can be an aid to the identification of needs for data, this decomposition is not of relevance in the final documentation of the data. Nevertheless, it may be useful to recor
22、d the functional needs and motivation which led to the identification of data along with the definition of those data. In the function oriented approaches the data are identified at the lowest level of decomposition of the functions. The identified data can be inputs to or outputs from the different
23、 functions. The identification of data separately in each function does not address and question the overall structure, design and definition of the data. Hence, the data definitions can continue to exist unharmonized and defined in such a way that they are unknowingly inefficient in use to the end
24、users. In the function oriented approaches separate design phases address the grouping of data into logical file structures, appropriate for the functions to be performed. These design phases take into account the access to and manipulation of data, but are usually not capable of reconsidering the o
25、verall design of data for that application. 2.3 Data design In the data oriented approaches the data are identified independently of functions. The analysts and designers: - observe the application area being administered by the organization; - design data definitions for that application area. The
26、primary objective of the data oriented approaches is to design efficient data definitions for the chosen application area. For the design of data, a deep knowledge of the application area being administered is required and must be acquired. The data definitions are important, because they can help t
27、he organization understand and perceive its functions and how it can perform its tasks. 3 Reference model 3.1 Overview The data oriented approach allows for partitioning all HMI specifications and all software into a layered architecture: - The external layer handles the presentation and manipulatio
28、n of data. It also handles mapping to and subsetting of the application data. - The application layer is that layer of the HMI reference model which is concerned with the definition of data and their behaviour. - The internal layer is outside the scope of HMI. The layer is supposed to take care of t
29、he internal storage, accessing, implementation and communication of data and their behaviour. Each layer of the layered architecture is partitioned into schemata, processes and populations. Data of each layer are mapped to data of adjacent layers only. A schema contains the data definitions, includi
30、ng constraints and derivation rules for the corresponding population data. A population contains the data instances which are enforced by a process according to the rules expressed in a corresponding schema. Only some aspects of the populations HMI(s) and Data base(s) are depicted in Figure 2. A pro
31、cess implements the enforcement of the rules found in a schema on the data instances in a corresponding population. The application layer is a centralized resource of application data and their behaviour. The specification of the common terminology and grammar of all HMI data is not dispersed into s
32、everal external functions, but is non-redundantly defined in the application schema. Recommendation 2.352 (03/93) 3 ITU-T RECMN*Z*352 93 m 4862571 0584326 301 m HMi(s) 4 processes External Application process processes internai -f3 bws) FIGURE 212.352 The three-layered architecture 3.2 Scope The sco
33、pe of the reference model of the HMI work is illustrated in Figure 3. The three-layered architecture is used only to define and illustrate the scope of the HMI and is not intended to impose restriction on the implementation. The three layers are: - the HMI external layer; - the HMI application layer
34、; - the HMI internal layer. The HMI application layer is controlled by one application schema, being a centralized resource, containing the specification of the structure and the dynamic behaviour of all HMI data. The HMI external layer can contain several external schemata. The external schemata sp
35、ecify the detailed concrete syntaxes (layout) at the HMI and the access rights for each presentation. The mappings between the application schema and the external schemata state the chosen subsetting and derivation for each presentation. The internal layer is outside the scope of HMI. The layer is s
36、upposed to take care of the internal storage, accessing, implementation and communication of data and their behaviour. The end users primarily use (the presentation of) HMI population data (instances), according to the external schema specifications. In order to know which presentations are availabl
37、e, the end users need access to the extemal schemata and their contents. However, the end users also need access to the definition of the data, their behaviour and interrelations. This information is provided from the application schema. The end users do not normally need access to the internal aspe
38、cts of the systems. The scope of the HMI work is therefore defined as consisting of the presentation and manipulation of - the HMI population data; - the HMI external schemata; - the HMI application schema. The end users requirements on the syntax and behaviour of the presentation of the HMI populat
39、ion data give requi- rements for the (presentation of the) external schemata. The (presentation of the) external schemata give requirements for the (presentation of the) application schema, which must be capable of specifying (the union of all) HMIs. 4 Recommendation 2.352 (03/93) ITU-T RECMN*Z-352
40、93 4862573 0584327 248 Scwe c4 H MI I I Subscriber O. TURAN Tel. No. Eau ip men t Year Colour 908016 1972 B 908017 1967 R 1967 R Subscriber Name (Suppressed) Tel. No. Tel. No. (Suppressed) No. Eauipment Year Cdour Subscriber Name (1,l) Tel. No. No. (1,l) Eau ipmen t Tel. No. Year (0,l) Colair Presen
41、tation of HMI population data (instances) Presentation of HMI external schemata (rules) Presentation of HMI application schema (rules) / I I , x 11 HMI external layer _ HMI application layer HMI internal layer rn intemal form of (instances) Database Exchange HMI population data TlCQ7640-9Yd03 NOTES
42、1 of HMI is shown to include the presentation of both the specifications in the external schemata (for the presentation of the HMI population data) and the common specifications in the application schema (for the structure and behaviour of the HMI population data). 2 The internal form and storage of
43、 data are shown in the bottom rectangle. The end users do not need to access to the internal form of the data. 3 The screen layouts and partitioning into windows are examples, illustrating the scope of HMI only, and are not intended to illustrate existing or toimpase future recommendations. The scre
44、en can contain graphics as weil, but that is not illustrated. Also, the database and the exchange are examples only. 4 squares represent processes. The tweway arrows represent population data flowing both ways. The scope of HMI is illustrated inside the upper rectangle. In addition to the population
45、 data, the scope Within the rectangles depicting the layers the small parallelograms represent schemata and the small Recommendation 2.352 (03/93) 5 FIGURE 312352 Scope of reference model ITU-T RECMN*Z.352 93 m 48b257L 0584328 189 = HMi(s) 3.3 The external schema is concerned with the specification
46、of data at the HMI for a specific presentation. A subdivision of the external schema is provided as follows (see Figure 4): the contents schema specifies the structure of the selected data and their relationships for a specific presentation; the layout schema specifies the way in which the data are
47、to be presented to the human user. The contents of the schemata and the mappings between the schemata provide specifications from the human (designers and users) point of view. These contents and mappings state nothing about the final implementation of the system. For example, all the specifications
48、 can be be compiled into one single functional block. Subdivision of the external layer - - Layout Contents Application process - processec + processes 4 External schemata Contents Application Internal schemata schemata schemata 1 I internai processes Ti 005190921604 FIGURE 4/2.352 Detailing of the
49、external schemata Annex A Guidelines for HMI developers (This annex forms an integral part of this Recommendation) A.1 Introduction This annex contains: - subclause A.2: Method; - subclause A.3: Data design. 6 Recommendation 2.352 (03193) ITU-T RECMNaZ.352 93 4862591 0584329 O10 E A.2 Method A.2.1 Purpose The purpose of the method is to: - identify the scope of human-machine interface specifications; - identify activities which are strictly needed in order to develop human-machine interfaces in accordance with the reference model of this Recommendation; - - identify nece
