1、ITU-T RECMN*F*?YO 73 Y862571 0585520 bY2 INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU OPERATIONS AND QUALITY OF SERVICE AUDIOVISUAL SERVICE F.740 (08/93) AUDIOVISUAL INTERACTIVE SERVICES ITU-T Recommendation F.740 (Previously “CCIlT Recommendation“) ITU
2、-T RECMN*F.740 93 4862593 0585523 589 FOREWORD The ITU-T (Telecommunication Standardization Sector) is a permanent organ of the International Telecommunication Union (ITU). The ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommen- dations on them with a vi
3、ew to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Conference (WTSC), which meets every four years, etablishes the topics for study by the IT-T Study Groups which, in their turn, produce Recommendations on these topics. The approval of Recommenda
4、tions by the Members of the ITU-T is covered by the procedure laid down in WTSC Resolution No. 1 (Helsinki, March 1-12, 1993). ITU-T Recommendation F.740 was prepared by ITU-T Study Group 1 (1993-1996) and was approved under the WTSC Resolution No. 1 procedure on the 31st of August 1993. NOTE In thi
5、s Recommendation, the expression “Administration” is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. 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 mechan
6、ical, including photocopying and microfilm, without permission in writing from the ITU. ITU-T RECMNxF.740 93 48b2591 0585522 41.5 W CONTENTS Page 1 Introduction : 1 2 Definition of the AV1 Service 1 3 Description of the AV1 Service 2 3.1 AV1 general aspects 2 3.2 The main roles 2 3.3 Their functiona
7、l needs 2 3.4 Terminal aspects 4 3.5 Terms and definitions . 4 . . 4 5 6 5 Procedures Charging principles 5 5.1 General 5 5.2 Networks capabilities for charging . 6 . 6 Quality of service 6.1 Network optimization . 6 6.2 Media quality 6 6.3 Security 6 . 7 Interworking and intercommunication requirem
8、ents . 6 7 Annex A -Examples of multimedia application . Recommenation F.740 (M3) i ITU-T RECMN*F.740 93 4862.593 0585523 351 Recommendation F.740 AUDIOVISUAL INTERACTIVE SERVICES (Geneva, 1993) The IT-T, considering (a) (b) (cl pictures on telecommunication networks; (d) retrieving applications con
9、trolling it, and thus, using a wide and complex range of functions; (e) (f) entertainment, etc., the existing (draft) documents on Audiovisual Interactive systems and protocols in SG 8; the state of the art of standardization of multimedia and hypermedia information in ISO; the need for handling aud
10、iovisual information of various types, namely text, graphics, still images and moving the need of having this audiovisual information shared by a various range of users supplying, managing or that users are justified to demand an acceptable minimum quality of service; the current setting up of both
11、pilot and operational AV1 Services in the fields of education, marketing help, adopts the subsequent Recommendation dealing with the General Description for Audiovisual Interactive Service (AVIS). 1 Introduction The purpose of this Recommendation is to define and describe, from the users point of vi
12、ew, the general features and attributes of the AV1 Service, regardless of the network environment where the service might be provided. 2 Definition of the AVI Service An AV1 Service is a service which provides, through appropriate access by standardized procedures, users of terminals or workstations
13、 with information which consists of various input and output presentation elements, possibly combined, such as: - texts; - graphics; - pictures; - audio sequences; - video sequences. A range of functions may be supplied to the user such as: - simple retrieval; - interactive consultation; - - re-arra
14、ngement of the assembling of elements; modification of the elements themselves. The AV1 Service also covers other service aspects related to the creation and management of the information. It is considered that the operation requires the participation of a number of organizations. The whole set of f
15、unctionalities offered by the AVI Service is usually carried out via telecommunications networks. The AV1 Service is essentially an asymmetrical service in which a single service provider is providing the service to several users. Additionally. rerouting from one service provider to another one may
16、be offered. The users of an AVI Service may be equipped with an heterogeneous set of terminals or workstations. Recommendstion F.740 (M3) 1 ITU-T RECMN*F.740 93 m 4862593 0585524 298 m 3 Description of the AV1 Service 3.1 AV1 general aspects Several types of users will be allowed to access the AV1 S
17、ervice. Different rights should be given to them. As an example, an author will need to make use of enhanced functions given by his AV1 terminai operating system and allowing him the access to remote systems when necessary via telecommunication networks whereas a simple retriever will remain more pa
18、ssive and simply need to consult the contents proposed by the AVI application. The information life cycle varies according to the type of application and can have different values on a scale from short to long. Three entities need to exchange information. Therefore, to set up an AV1 application, tel
19、ecommunications will be used. 3.2 The main roles The AV1 Service provides with facilities to fulfil the requirements of the users involved in creating, exchanging, modifying, managing and executing AV1 applications. The users of the AV1 Service may have several roles: - author; - information manager
20、; - preparer; - retriever, dealing with the following families of functions: - editing functions; - information management functions; - execution and retrieval functions. According to the users needs, various and numerous exchanges will be set up between systems or subsystems providing with the func
21、tions. An AV1 Service can be illustrated as in the Figure: FIGURE 1F.740 An AV1 service 3.3 Their functional needs Each of the various roles has specific functional requirements with regards to the first three families of functions identified i.e. editing, information management, execution. 2 Recomm
22、endation F.740 (08/93) ITU-T RECMN*F.740 93 m 4Bb2591 0585525 124 m As the respective locations of entities assuring roles and systems supplying functions may be distant, exchange functions should be activated as well. Table 1 hereafter, breaks down the needs of the four categories of roles accordin
23、g to the three families of functions. TABLE 1F.740 Roles versus functional requirements Editing - AV1 creation or updating - Creation of the catalogue for AVIs already edited - Modification of AVIS already edited - Validation and transmission to information management system - Concatenation of AVIs
24、already edited - Consultation of catalogues of AVIS already edited - Transmission to information management of AVIs already edited or their updates Functions Information Management - Management of edited AVIS and updates - Usage follow-up, trace processing - Statistics and payment - Creation and mai
25、ntenance of catalogue for AVIs ready for management - Storage of AVIs and updates - Implementation of a pricing policy - Delivery management (profile verification) - Retriever and preparer management (access control, billing, . . .) - Choice of AVIS already managed - Negotiation of configuration, pa
26、rameters and installation on real supports as required - Sending of retriever usage follow-up Execution - Debugging of AVIS - Experimentation using a sample user group Roles Author Information Manager Preparer Retriever Two concrete examples of AV1 applications are given in Annex A. - Choice of AVIS
27、 already managed - Usage follow-up - Recovery management - Collection of execution traces and recovery context - Reception and installation of AVIS and updates - Verification of correct installation - Collection of traces generated by AVIS - Choice of AVIS already installed - Recovery management (No
28、te) - AVIusage Recommendation F.740 (OW93) 3 ITU-T RECMN*F-740 93 Li862591 0585526 Ob0 W 3.4 Terminai aspects Terminal equipment needs to provide with a set of functions such as: - - reproduction of sound; - acquisition of user interactions. display of text, graphics, still images preferably in colo
29、ur and optionally moving images: All these functions should make use of appropriate standards defined or being defined in IS0 EC/JTC 1 and ITU-T. Terminals will be connected to appropriate networks by making use of interfaces and protocols defined in ITU-T. Terminals are equipped with a minimum set
30、of items, namely a keypad, mouse, monitor and loudspeaker. 3.5 Terms and definitions 3.5.1 Specific terminology For the purpose of this Recommendation, the following dinitions apply: role: The role is either a person who activates, or a process which has been designed by a person in order to activat
31、e a functionality of an AV1 application. retriever: The role who mainly consults the application by interacting with the presentation process. preparer: The role who mainly selects, installs, personalizes and concatenates the applications as well as following up their execution. information manager:
32、 The role who mainly defines or modifies user access authorization and tariffing, then provides the execution process with the applications to be executed or their updates. author: The role who mainly creates and validates applications or updates and supplies them to the information manager for thei
33、r distribution. editing: Creation of applications, including design, use of media, development, verification, modification, updating and validation before the applications become available to the users. information management: Application management, including storage, classification. catalogue crea
34、tion and management, retriever and preparer management, tarification, monitoring usage processing, context recovery management, etc. execution: Application usage after installation, user interface management, monitoring usage implementation and, where appropriate, upstream connection with an informa
35、tion management system or directly with an editing system in case of an implementation in progress. AV1 application: An AV1 application is a dedicated use of the AV1 Service to satisfy a particular requirement. An AV1 application contains at least structural and presentation elements. The presentati
36、on elements are either input or output objects of various nature. They may be of monomedia, multimedia or hypermedia type. The execution of an AV1 application consists in activating scriptware transferred as part of the application and forming its structural elements. These scriptware may perform, a
37、mong others, the following functions: - - global control of events; - requests for traces; - - - references to other scriptware; - response analysis. references to and links between objects; check-points management for navigation and warm-state recovery; invocation of external processes and data; 4
38、Recommendation F.740 (W3) ITU-T RECMN*F.740 93 m 4862591 O585527 TT7 m AV1 terminal: The particular configuration of an AVI terminal will depend on the role which will use it. As an example, an author will make use of a scanner on his AV1 terminal whereas a retriever will need to consult one or seve
39、ral contents by simply reproducing them on his AV1 terminal. update: Part of an application which results from the comparison between a given version of an application with a previous one. 3.5.2 Terms and definitions shared with IS0 IEC JTC YSC 29NyG 12-MHEG multimedia (representation): The property
40、 of handling several types of representation media. The term multimedia is an adjective, it must be used attached to a noun which helps defining the context; multimedia service or application. multimedia terminal, multimedia network, multimedia presentation. In the MHEG standard, multimedia is used
41、in the sense of multiple representation media. “Multimedia” starts with two types of representation media in a piece of information and thus a remote processing service or videotex when using only a usual keyboard and a purely textual display cannot be said multimedia as involving only one type of m
42、edium (character or text type), although in both directions, to and from the user (the service is interactive, not multimedia). hypermedia: The ability to access monomedia and multimedia information by interaction with explicit links. Example - a set of linked photographic pictures with associated s
43、ound sequences showing the famous buildings in a given town together with different views of each building; the pictures and sounds will be accessed through navigation along the predefined links within the object. object: Coded representation of a finite independent selfdefined piece of information
44、that can be manipulated as a whole by applications and interchanged as one unit. The information can be of multiple different types: content, projector, basic, generic input, spatio-temporal composite, clock, conditional action set and null. NOTE - This definition is not restricted to digitally code
45、d objects, there could also be analogue objects such as videodisc sequence. script: Specification of how one or more objects are to be presented to, or input from a user. scriptware (script software): Software that realizes a script, including both informative data and associated data about how the
46、information is to be handldpresented. 4 Procedures It is essential that the access to the service, from the users point of view, should be offered via a common look-and-feel for any user on any kind of implementation of it. A guidance, taking the shape of a dialogue between the user and the system o
47、perating the application, will offer the user indications and controls information. 5 Charging principles 5.1 General Depending on the kind of applications offered by the service or the kind of users, namely author, information manager or retriever and general public or professional accessing it, va
48、rious charging principles should have to be set up. As an example, a general public user accessing an application offered by the service via a public and unattended equipment should access his service free of charge, whereas an author should subscribe to a private subscribers group and additionally,
49、 pay for the retrieval of the available information. An essential requirement is that charging must correspond to the service offered taking into account the nature of both users and applications accessed by them. Recommendation E740 (M3) 5 ITU-T RECMN*F=740 93 W 48b259L 0585528 933 5.2 Networks capabilities for charging This Recommendation does not cover detailed charging principles which are to be defined in other contexts. The network should be able to charge for the use of the service on the following basis: - no charging; or - pay per call; and/or - pay per dura
