IEC 63478-2:2025
(Main)User’s quality of experience on multimedia conferencing services - Part 2: Requirements
User’s quality of experience on multimedia conferencing services - Part 2: Requirements
IEC 63478-2:2025 describes the requirements to measure users’ quality of experience (QoE) on multimedia conferencing services.
Qualité de l'expérience de l'utilisateur pour les services de conférence multimédia- Partie 2: Exigences
L'IEC 63478-2:2025 décrit les exigences pour mesurer la qualité de l'expérience (QoE) des utilisateurs pour les services de conférence multimédia.
General Information
Standards Content (Sample)
IEC 63478-2 ®
Edition 1.0 2025-10
INTERNATIONAL
STANDARD
User’s quality of experience on multimedia conferencing services -
Part 2: Requirements
ICS 33.160.60 ISBN 978-2-8327-0737-1
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or
by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either
IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC copyright
or have an enquiry about obtaining additional rights to this publication, please contact the address below or your local
IEC member National Committee for further information.
IEC Secretariat Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.
About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.
IEC publications search - IEC Products & Services Portal - products.iec.ch
webstore.iec.ch/advsearchform Discover our powerful search engine and read freely all the
The advanced search enables to find IEC publications by a publications previews, graphical symbols and the glossary.
variety of criteria (reference number, text, technical With a subscription you will always have access to up to date
committee, …). It also gives information on projects, content tailored to your needs.
replaced and withdrawn publications.
Electropedia - www.electropedia.org
The world's leading online dictionary on electrotechnology,
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published containing more than 22 500 terminological entries in English
details all new publications released. Available online and and French, with equivalent terms in 25 additional languages.
once a month by email. Also known as the International Electrotechnical Vocabulary
(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc
If you wish to give us your feedback on this publication or
need further assistance, please contact the Customer
Service Centre: sales@iec.ch.
CONTENTS
FOREWORD . 2
INTRODUCTION . 4
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and abbreviated terms . 5
3.1 Terms and definitions. 5
3.2 Abbreviated terms . 5
4 Overview . 5
5 QoE parameters . 6
5.1 General . 6
5.2 Video quality . 7
5.3 Audio quality . 8
5.4 Synchronization . 8
5.5 Accessibility . 9
5.6 Interoperability . 9
5.7 Participation . 10
5.8 Openness . 10
5.9 UI and UX . 10
6 Requirements for QoE functional operations . 11
6.1 General . 11
6.2 QoE initialization . 12
6.3 QoE monitoring . 12
6.4 QoE evaluation . 13
7 Requirements for QoE functional entities . 13
7.1 General . 13
7.2 Multimedia conferencing server (MCS) . 14
7.3 Multimedia conferencing client (MCC) . 14
7.4 QoE measurement agent (QMA) . 14
7.5 QoE measurement manager (QMM) . 14
Bibliography . 15
Figure 1 – Functional entities and operations for QoE measurement . 11
Table 1 – List of parameters for QoE measurement . 7
Table 2 – Requirements for QoE functional entities . 13
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
User’s quality of experience on multimedia conferencing services -
Part 2: Requirements
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 63478-2 has been prepared by IEC technical committee TC 100: Audio, video and
multimedia systems and equipment. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
100/4246/CDV 100/4339/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 63478 series, published under the general title User’s quality of
experience on multimedia conferencing services, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
INTRODUCTION
With the global COVID-19 pandemic, meetings for business and education purposes shifted
from face-to-face to virtual. Consequently, a range of multimedia conferencing services were
developed, enabling users to choose and enjoy conferencing services based on personal
preferences. To ensure optimal user experience, it is essential to measure the quality of
experience (QoE) for multimedia conferencing services. However, there is currently a lack of
standardized methods for measuring a user's QoE in this context. Thus, there is a pressing
need to provide standards for measuring and evaluating a user's QoE for multimedia
conferencing services.
Traditionally, quality of service (QoS) has been measured for network data communication,
represented by objective index values like delay, throughput, and jitter. In contrast, QoE
represents a user's level of satisfaction with a specific service and reflects a human emotional
quality. As such, QoE is subject to overall service performance from the user's perspective. In
the case of multimedia conferencing services, measuring QoE is challenging due to varying
user preferences, as well as varying services and application characteristics. Therefore, a
unified framework is necessary to measure and evaluate a user's QoE for multimedia
conferencing services.
This document aims to provide standards for enhancing a user's QoE for multimedia
conferencing services. The IEC 63478 series specifies general considerations and
requirements to enhance a user's QoE and measurement methods for associated QoE
parameters.
The IEC 63478 series consists of the following parts:
– Part 1: General;
– Part 2: Requirements; and
– Part 3: Measurement methods .
IEC 63478-1 (Technical Report) describes general considerations to measure users’ QoE.
IEC 63478-2 (International Standard) describes the requirements to be considered to measure
users’ QoE.
IEC 63478-3 (International Standard) describes the measurement methods for QoE
parameters.
___________
Under preparation. Stage at time of publication: IEC CDV 63478-3:2025.
Under preparation. Stage at time of publication: IEC CDV 63478-3:2025.
1 Scope
This part of IEC 63478 describes the requirements to measure users’ quality of experience
(QoE) on multimedia conferencing services.
2 Normative references
There are no normative references in this document.
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
3.2 Abbreviated terms
Abbreviated term Full term
API/SDK Application programming interface / Software development kit
MCC Multimedia conferencing client
MCS Multimedia conferencing server
QMA QoE measurement agent
QMM QoE measurement manager
QoE Quality of experience
UI User interface
UX User experience
4 Overview
One crucial aspect of multimedia conferencing services is the quality of experience (QoE),
which describes a user's overall satisfaction level with a particular service. It measures how
well a service meets users' expectations and needs and can be influenced by various factors
including audio and video quality, responsiveness, reliability and ease of use. As the use of
multimedia conferencing services for remote communication increases, the importance of
measuring user QoE also increases. Reliable and high-quality services that meet user
expectations are essential for continued use and to prevent users from switching to other
providers. Therefore, a QoE measurement standard for multimedia conferencing services is
required to ensure a consistent and high-quality user experience across various platforms,
services and devices.
Moreover, QoE measurement standards can help service providers optimize their services and
identify areas for improvement. By measuring and analyzing QoE, service providers can identify
service problems and take corrective action to improve service quality. QoE measurement
standards allow service providers to compare services with other providers and benchmark
service quality. The complex nature of multimedia communications underscores the need for
QoE measurement standards in multimedia conferencing services. Quality issues such as
latency, jitter, packet loss and network congestion can affect the user experience and degrade
QoE, making it essential to measure and optimize QoE to provide a high-quality user experience.
The key factors for effective QoE measurement include the QoE parameters to be measured
and the QoE measurement operations to be performed among the QoE functional entities.
These QoE parameters are subdivided into QoE factors, which are classified into 'mandatory'
and 'optional' depending on their impact on QoE. The QoE measurement in multimedia
conferencing services can be measured by measuring the QoE factor, which is measured
through the operation between functional entities. To measure QoE, the following operations
are required.
a) QoE initialization: This is a procedure for parameter negotiation and measurement method
negotiation between QoE functional entities when a multimedia service begins.
b) QoE monitoring: This is the process of measuring parameters and aggregating the
measured QoE parameter values to measure the QoE of multimedia services.
c) QoE evaluation: This is the process of analysis of the aggregated QoE parameters by QMM
and report of QoE measurement results to MCS.
The QoE in multimedia conferencing services shall be measured through these requirements
for QoE measurement.
5 QoE parameters
5.1 General
To measure users’ QoE for multimedia conferencing services, it is necessary to consider a
variety of QoE parameters, which can consist of video quality, audio quality, video and audio
synchronization, accessibility, interconnectivity, openness, participation and UI/UX as
described in Table 1. Each QoE parameter can be measured with a set of QoE factors. Some
QoE factors shall be used as mandatory for effective QoE measurement, whereas the others
may be employed optionally. For measurement of a specific QoE factor, subjective and/or
objective approaches can be used. Subjective measurement is based on user feedback,
whereas objective measurement is based on the quantitative measurement of multimedia
conferencing services. The detailed method of QoE parameters shall be negotiated among the
concerned QoE functional entities.
Table 1 – List of parameters for QoE measurement
QoE parameter QoE factor Mandatory/optional
Visual clarity Mandatory
Video quality
Latency Mandatory
Clarity Mandatory
Noise Mandatory
Audio quality Latency Mandatory
Dynamic range Optional
Echo cancellation Optional
Accuracy Mandatory
Synchronization Adaptive Optional
Consistency Optional
Support for assistive technologies Mandatory
Accessibility Compatibility with assistive devices Optional
Captioning and transcription Mandatory
Cross-platform compatibility Mandatory
Interoperability Integration with other services Mandatory
Security Mandatory
User group size Mandatory
Participation
Collaboration tools Mandatory
Transparency Optional
Openness
Open API/SDK Optional
Intuitive and user-friendly design Mandatory
Consistency across platforms Optional
UI and UX
Customizability Optional
Feedback and notifications Mandatory
5.2 Video quality
Video quality is a critical factor in measuring QoE in multimedia conferencing services, as it
determines the perceived visual clarity and smoothness of the video stream during multimedia
conferencing services. Video quality is affected by several factors such as network bandwidth
and latency. Service providers can also provide settings and tools for users to adjust the video
quality to suit their specific needs and preferences.
To measure the video quality of multimedia conferencing services, the required QoE parameters
include the following:
– Visual clarity
Service providers should ensure that their services deliver high visual clarity to ensure that
users can clearly see other participa
...
IEC 63478-2 ®
Edition 1.0 2025-10
NORME
INTERNATIONALE
Qualité de l'expérience de l'utilisateur pour les services de conférence
multimédia –
Partie 2: Exigences
ICS 33.160.60 ISBN 978-2-8327-0737-1
Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et
les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.
IEC Secretariat Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.
A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.
Recherche de publications IEC - IEC Products & Services Portal - products.iec.ch
webstore.iec.ch/advsearchform Découvrez notre puissant moteur de recherche et consultez
La recherche avancée permet de trouver des publications gratuitement tous les aperçus des publications, symboles
IEC en utilisant différents critères (numéro de référence, graphiques et le glossaire. Avec un abonnement, vous aurez
texte, comité d’études, …). Elle donne aussi des toujours accès à un contenu à jour adapté à vos besoins.
informations sur les projets et les publications remplacées
ou retirées. Electropedia - www.electropedia.org
Le premier dictionnaire d'électrotechnologie en ligne au
IEC Just Published - webstore.iec.ch/justpublished monde, avec plus de 22 500 articles terminologiques en
Restez informé sur les nouvelles publications IEC. Just anglais et en français, ainsi que les termes équivalents
dans 25 langues additionnelles. Egalement appelé
Published détaille les nouvelles publications parues.
Disponible en ligne et une fois par mois par email. Vocabulaire Electrotechnique International (IEV) en ligne.
Service Clients - webstore.iec.ch/csc
Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-
nous: sales@iec.ch.
SOMMAIRE
AVANT-PROPOS . 2
INTRODUCTION . 4
1 Domaine d'application . 5
2 Références normatives . 5
3 Termes, définitions et termes abrégés . 5
3.1 Termes et définitions . 5
3.2 Termes abrégés . 5
4 Vue d'ensemble . 5
5 Paramètres de QoE . 6
5.1 Généralités . 6
5.2 Qualité vidéo. 7
5.3 Qualité audio . 8
5.4 Synchronisation . 8
5.5 Accessibilité . 9
5.6 Interopérabilité . 10
5.7 Participation . 10
5.8 Ouverture . 11
5.9 UI et UX . 11
6 Exigences relatives aux opérations fonctionnelles de QoE . 12
6.1 Généralités . 12
6.2 Initialisation de la QoE . 13
6.3 Surveillance de la QoE . 13
6.4 Évaluation de la QoE . 14
7 Exigences relatives aux entités fonctionnelles de QoE . 14
7.1 Généralités . 14
7.2 Serveur de conférence multimédia (MCS) . 14
7.3 Client de conférence multimédia (MCC) . 15
7.4 Agent de mesure de QoE (QMA) . 15
7.5 Gestionnaire de mesure de QoE (QMM) . 15
Bibliographie . 16
Figure 1 – Entités et opérations fonctionnelles pour le mesurage de la QoE . 12
Tableau 1 – Liste des paramètres pour le mesurage de la QoE . 7
Tableau 2 – Exigences relatives aux entités fonctionnelles de QoE . 14
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
Qualité de l'expérience de l'utilisateur pour
les services de conférence multimédia -
Partie 2: Exigences
AVANT-PROPOS
1) La Commission Électrotechnique Internationale (IEC) est une organisation mondiale de normalisation composée
de l'ensemble des comités électrotechniques nationaux (Comités nationaux de l'IEC). L'IEC a pour objet de
favoriser la coopération internationale pour toutes les questions de normalisation dans les domaines de
l'électricité et de l'électronique. À cet effet, l'IEC – entre autres activités – publie des Normes internationales,
des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au public (PAS) et des
Guides (ci-après dénommés "Publication(s) de l'IEC"). Leur élaboration est confiée à des comités d'études, aux
travaux desquels tout Comité national intéressé par le sujet traité peut participer. Les organisations
internationales, gouvernementales et non gouvernementales, en liaison avec l'IEC, participent également aux
travaux. L'IEC collabore étroitement avec l'Organisation Internationale de Normalisation (ISO), selon des
conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de l'IEC concernant les questions techniques représentent, dans la mesure du
possible, un accord international sur les sujets étudiés, étant donné que les Comités nationaux de l'IEC intéressés
sont représentés dans chaque comité d'études.
3) Les Publications de l'IEC se présentent sous la forme de recommandations internationales et sont agréées
comme telles par les Comités nationaux de l'IEC. Tous les efforts raisonnables sont entrepris afin que l'IEC
s'assure de l'exactitude du contenu technique de ses publications; l'IEC ne peut pas être tenue responsable de
l'éventuelle mauvaise utilisation ou interprétation qui en est faite par un quelconque utilisateur final.
4) Dans le but d'encourager l'uniformité internationale, les Comités nationaux de l'IEC s'engagent, dans toute la
mesure possible, à appliquer de façon transparente les Publications de l'IEC dans leurs publications nationales
et régionales. Toutes divergences entre toutes Publications de l'IEC et toutes publications nationales ou
régionales correspondantes doivent être indiquées en termes clairs dans ces dernières.
5) L'IEC elle-même ne fournit aucune attestation de conformité. Des organismes de certification indépendants
fournissent des services d'évaluation de conformité et, dans certains secteurs, accèdent aux marques de
conformité de l'IEC. L'IEC n'est responsable d'aucun des services effectués par les organismes de certification
indépendants.
6) Tous les utilisateurs doivent s'assurer qu'ils sont en possession de la dernière édition de cette publication.
7) Aucune responsabilité ne doit être imputée à l'IEC, à ses administrateurs, employés, auxiliaires ou mandataires,
y compris ses experts particuliers et les membres de ses comités d'études et des Comités nationaux de l'IEC,
pour tout préjudice causé en cas de dommages corporels et matériels, ou de tout autre dommage de quelque
nature que ce soit, directe ou indirecte, ou pour supporter les coûts (y compris les frais de justice) et les dépenses
découlant de la publication ou de l'utilisation de cette Publication de l'IEC ou de toute autre Publication de l'IEC,
ou au crédit qui lui est accordé.
8) L'attention est attirée sur les références normatives citées dans cette publication. L'utilisation de publications
référencées est obligatoire pour une application correcte de la présente publication.
9) L'IEC attire l'attention sur le fait que la mise en application du présent document peut entraîner l'utilisation d'un
ou de plusieurs brevets. L'IEC ne prend pas position quant à la preuve, à la validité et à l'applicabilité de tout
droit de brevet revendiqué à cet égard. À la date de publication du présent document, l'IEC n'avait pas reçu
notification qu'un ou plusieurs brevets pouvaient être nécessaires à sa mise en application. Toutefois, il y a lieu
d'avertir les responsables de la mise en application du présent document que des informations plus récentes
sont susceptibles de figurer dans la base de données de brevets, disponible à l'adresse https://patents.iec.ch ou
www.iso.org/patents. L'IEC ne saurait être tenue pour responsable de ne pas avoir identifié de tels droits de
brevets.
L'IEC 63478-2 a été établie par le comité d'études 100 de l'IEC: Systèmes et équipements audio,
vidéo et services de données. Il s'agit d'une Norme internationale.
Le texte de cette Norme internationale est issu des documents suivants:
Projet Rapport de vote
100/4246/CDV 100/4339/RVC
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant
abouti à son approbation.
La langue employée pour l'élaboration de cette Norme internationale est l'anglais.
Ce document a été rédigé selon les Directives ISO/IEC, Partie 2, il a été développé selon les
Directives ISO/IEC, Partie 1 et les Directives ISO/IEC, Supplément IEC, disponibles sous
www.iec.ch/members_experts/refdocs. Les principaux types de documents développés par
l'IEC sont décrits plus en détail sous www.iec.ch/publications.
Une liste de toutes les parties de la série IEC 63478, publiées sous le titre général Qualité de
l'expérience de l'utilisateur pour les services de conférence multimédia, se trouve sur le site
web de l'IEC.
Le comité a décidé que le contenu de ce document ne sera pas modifié avant la date de stabilité
indiquée sur le site web de l'IEC sous webstore.iec.ch dans les données relatives au document
recherché. À cette date, le document sera
– reconduit,
– supprimé, ou
– révisé.
INTRODUCTION
Avec la pandémie mondiale de COVID-19, les réunions à des fins professionnelles et
éducatives sont passées d'un mode en présence au mode virtuel. Par conséquent, une gamme
de services de conférence multimédia a été développée, ce qui permet aux utilisateurs de
choisir et de profiter des services de conférence selon leurs préférences personnelles. Pour
assurer une expérience utilisateur optimale, il est essentiel de mesurer la qualité de
l'expérience (QoE) des services de conférence multimédia. Toutefois, il n'existe actuellement
aucune méthode normalisée pour mesurer la QoE d'un utilisateur dans ce contexte. Il est donc
impérativement nécessaire de fournir des normes pour mesurer et évaluer la QoE de l'utilisateur
pour les services de conférence multimédia.
Traditionnellement, la qualité de service (QoS, Quality of Service) a été mesurée pour la
communication de données réseau, représentée par des valeurs d'index objectives comme le
délai, le débit et la gigue. En revanche, la QoE représente le niveau de satisfaction d'un
utilisateur à l'égard d'un service spécifique et reflète la qualité émotionnelle humaine. À ce titre,
la QoE dépend des performances de service globales du point de vue de l'utilisateur. Dans le
cas des services de conférence multimédia, la mesure de la QoE est difficile à réaliser en raison
de la diversité des préférences des utilisateurs et des caractéristiques des services et des
applications. Un cadre unifié est donc nécessaire pour mesurer et évaluer la QoE de l'utilisateur
pour les services de conférence multimédia.
Le présent document vise à fournir des normes pour améliorer la QoE de l'utilisateur pour les
services de conférence multimédia. La série IEC 63478 définit des considérations générales et
des exigences pour améliorer la QoE de l'utilisateur, ainsi que des méthodes de mesure des
paramètres de QoE associés.
La série IEC 63478 est composée des parties suivantes:
– Partie 1: Généralités;
– Partie 2: Exigences; et
– Partie 3: Méthodes de mesurage .
L'IEC 63478-1 (Rapport technique) décrit des considérations générales pour mesurer la QoE
des utilisateurs.
L'IEC 63478-2 (Norme internationale) décrit les exigences à prendre en compte pour mesurer
la QoE des utilisateurs.
L'IEC 63478-3 (Norme internationale) décrit les méthodes de mesurage des paramètres de
QoE.
___________
En cours d'élaboration. Stade au moment de la publication: IEC CDV 63478-3:2025.
En cours d'élaboration. Stade au moment de la publication: IEC CDV 63478-3:2025.
1 Domaine d'application
La présente partie de l'IEC 63478 décrit les exigences pour mesurer la qualité de l'expérience
(QoE) des utilisateurs pour les services de conférence multimédia.
2 Références normatives
Le présent document ne contient aucune référence normative.
3 Termes, définitions et termes abrégés
3.1 Termes et définitions
Aucun terme n'est défini dans le présent document.
L'ISO et l'IEC tiennent à jour des bases de données terminologiques destinées à être utilisées
en normalisation, consultables aux adresses suivantes:
– IEC Electropedia: disponible à l'adresse https://www.electropedia.org/
– ISO Online browsing platform: disponible à l'adresse https://www.iso.org/obp
3.2 Termes abrégés
Terme abrégé Terme complet
API/SDK (Application Programming Interface / Software development kit) Interface de programmation
d'application / kit de développement logiciel
MCC (Multimedia conferencing client) Client de conférence multimédia
MCS (Multimedia conferencing server) Serveur de conférence multimédia
QMA (QoE measurement agent) Agent de mesure de QoE
QMM (QoE measurement manager) Gestionnaire de mesure de QoE)
QoE (Quality of experience) Qualité de l'expérience
UI (User interface) Interface utilisateur
UX (User experience) Expérience utilisateur
4 Vue d'ensemble
L'un des aspects essentiels des services de conférence multimédia est la qualité de
l'expérience (QoE), qui décrit le niveau global de satisfaction d'un utilisateur vis-à-vis d'un
service particulier. Elle mesure dans quelle mesure un service satisfait aux attentes et aux
besoins des utilisateurs et peut être influencée par différents facteurs, notamment la qualité
audio et vidéo, la réactivité, la fiabilité et la facilité d'utilisation. Avec l'augmentation de
l'utilisation des services de conférence multimédia pour les communications à distance,
l'importance du mesurage de la QoE de l'utilisateur augmente également. Des services fiables
et de haute qualité qui répondent aux attentes des utilisateurs sont essentiels pour que ceux-
ci continuent à les utiliser et pour éviter qu'ils ne se tournent vers d'autres fournisseurs. Par
conséquent, une norme de mesure de la QoE pour les services de conférence multimédia est
exigée pour assurer une expérience utilisateur uniforme et de haute qualité sur différentes
plateformes, services et appareils.
De plus, les normes de mesure de la QoE peuvent aider les fournisseurs de services à optimiser
leurs services et à identifier les domaines à améliorer. En mesurant et en analysant la QoE, les
fournisseurs de services peuvent identifier les problèmes de service et prendre des mesures
correctives pour améliorer la qualité du service. Les normes de mesure de la QoE permettent
aux fournisseurs de services de comparer leurs services avec ceux d'autres fournisseurs et
d'évaluer la qualité des services. La complexité des communications multimédias souligne la
nécessité d'établir des normes de mesure de la QoE pour les services de conférence multimédia.
Les problèmes de qualité tels que la latence, la gigue, la perte de paquets et la congestion du
réseau peuvent compromettre l'expérience utilisateur et dégrader la QoE, ce qui rend essentiel
de mesurer et d'optimiser la QoE afin de fournir une expérience utilisateur de haute qualité.
Les principaux facteurs de mesure efficace de la QoE incluent les paramètres de QoE à mesurer
et les opérations de mesurage de la QoE à effectuer parmi les entités fonctionnelles de la QoE.
Ces paramètres de QoE sont subdivisés en facteurs QoE, qui sont classés en "obligatoires" et
en "facultatifs" en fonction de leur impact sur la QoE. Le mesurage de la QoE pour les services
de conférence multimédia peut être effectué en mesurant le facteur QoE, qui est mesuré par le
fonctionnement entre entités fonctionnelles. Pour mesurer la QoE, les opérations suivantes
sont exigées.
a) Initialisation de la QoE: Il s'agit d'une procédure de négociation des paramètres et de la
méthode de mesurage entre entités fonctionnelles de la QoE lors du démarrage d'un service
multimédia.
b) Surveillance de la QoE: Il s'agit du processus de mesurage des paramètres et d'agrégation
des valeurs de paramètres de QoE mesurées pour mesurer la QoE sur les services
multimédias.
c) Évaluation de la QoE: Il s'agit du processus d'analyse des paramètres de QoE agrégés par
QMM et de la communication des résultats du mesurage de la QoE au MCS.
La QoE pour les services de conférence multimédia doit être mesurée à l'aide de ces exigences
de mesurage de la QoE.
5 Paramètres de QoE
5.1 Généralités
Pour mesurer la QoE des utilisateurs pour les services de conférence multimédia, il est
nécessaire de prendre en compte différents paramètres de QoE, qui peuvent inclure la qualité
vidéo, la qualité audio, la synchronisation vidéo et audio, l'accessibilité, l'interconnectivité,
l'ouverture, la participation et l'interface/expérience utilisateur, comme cela est décrit dans le
Tableau 1. Chaque paramètre de QoE peut être mesuré avec un ensemble de facteurs QoE.
Certains facteurs QoE doivent être utilisés comme obligatoires pour un mesurage efficace de
la QoE, tandis que les autres peuvent être utilisés à titre facultatif. Pour le mesurage d'un
facteur QoE spécifique, les approches subjectives et/ou objectives peuvent être utilisées. Le
mesurage subjectif repose sur les retours des utilisateurs, tandis que le mesurage objectif
repose sur le mesurage quantitatif des services de conférence multimédia. La méthode détaillée
des paramètres de QoE doit être négociée entre les entités fonctionnelles QoE concernées.
Tableau 1 – Liste des paramètres pour le mesurage de la QoE
Paramètre de QoE Facteur QoE Obligatoire/ facultatif
Clarté visuelle Obligatoire
Qualité vidéo
Temps de latence Obligatoire
Clarté Obligatoire
Bruit Obligatoire
Qualité audio Temps de latence Obligatoire
Plage dynamique Facultatif
Annulation de l'écho Facultatif
Exactitude Obligatoire
Synchronisation Adaptative Facultatif
Cohérence Facultatif
Prise en charge des technologies d'assistance Obligatoire
Accessibilité Compatibilité avec les dispositifs d'assistance Facultatif
Sous-titrage et transcription Obligatoire
Compatibilité multiplateforme Obligatoire
Interopérabilité Intégration à d'autres services Obligatoire
Sécurité Obligatoire
Taille du groupe d'utilisateurs Obligatoire
Participation
Outils de collaboration Obligatoire
Transparence Facultatif
Ouverture
API/SDK ouverts Facultatif
Conception intuitive et conviviale Obligatoire
Cohérence entre les plateformes Facultatif
UI et UX
Possibilité de personnalisation Facultatif
Retour d'information et notifications Obligatoire
5.2 Qualité vidéo
La qualité vidéo est un facteur essentiel pour mesurer la QoE dans les services de conférence
multimédia, car elle détermine la clarté visuelle perçue et la fluidité du flux vidéo pendant les
services de conférence multimédia. La qualité vidéo est affectée par plusieurs facteurs, tels
que la bande passante et la latence du réseau. Les fournisseurs de services peuvent également
fournir des réglages et des outils qui permettent aux utilisateurs d'ajuster la qualité vidéo en
fonction de leurs besoins et préférences spécifiques.
Pour mesurer la qualité vidéo des services de conférence multimédia, les paramètres de QoE
exigés sont les suivants:
– Clarté visuelle
Il convient que les fournisseurs de services s'assurent que leurs services apportent une
grande clarté visuelle afin que les utilisateurs puissent voir clairement les autres participants
et leurs supports visuels lors des réunions.
– Temps de latence
La latence est le délai entre le moment où les données vidéo sont capturées et le moment
où elles s'affichent à l'écran. Une latence élevée peut entraîner des problèmes tels que des
bégaiements et des arrêts sur image, ce qui peut affecter le niveau de QoE.
Des méthodes générales pour évaluer les systèmes de communication audio et vidéo sont
décrites dans l'IEC 62251, qui peut servir de référence à titre informatif pour l'évaluation des
services de c
...
IEC 63478-2 ®
Edition 1.0 2025-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
User’s quality of experience on multimedia conferencing services -
Part 2: Requirements
Qualité de l'expérience de l'utilisateur pour les services de conférence
multimédia –
Partie 2: Exigences
ICS 33.160.60 ISBN 978-2-8327-0737-1
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or
by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either
IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC copyright
or have an enquiry about obtaining additional rights to this publication, please contact the address below or your local
IEC member National Committee for further information.
Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et
les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.
IEC Secretariat Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.
About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.
IEC publications search - IEC Products & Services Portal - products.iec.ch
webstore.iec.ch/advsearchform Discover our powerful search engine and read freely all the
The advanced search enables to find IEC publications by a publications previews, graphical symbols and the glossary.
variety of criteria (reference number, text, technical With a subscription you will always have access to up to date
committee, …). It also gives information on projects, content tailored to your needs.
replaced and withdrawn publications.
Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published containing more than 22 500 terminological entries in English
details all new publications released. Available online and and French, with equivalent terms in 25 additional languages.
once a month by email. Also known as the International Electrotechnical Vocabulary
(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc
If you wish to give us your feedback on this publication or
need further assistance, please contact the Customer
Service Centre: sales@iec.ch.
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.
A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.
Recherche de publications IEC - IEC Products & Services Portal - products.iec.ch
webstore.iec.ch/advsearchform Découvrez notre puissant moteur de recherche et consultez
La recherche avancée permet de trouver des publications gratuitement tous les aperçus des publications, symboles
IEC en utilisant différents critères (numéro de référence, graphiques et le glossaire. Avec un abonnement, vous aurez
texte, comité d’études, …). Elle donne aussi des toujours accès à un contenu à jour adapté à vos besoins.
informations sur les projets et les publications remplacées
ou retirées. Electropedia - www.electropedia.org
Le premier dictionnaire d'électrotechnologie en ligne au
IEC Just Published - webstore.iec.ch/justpublished monde, avec plus de 22 500 articles terminologiques en
Restez informé sur les nouvelles publications IEC. Just anglais et en français, ainsi que les termes équivalents
Published détaille les nouvelles publications parues. dans 25 langues additionnelles. Egalement appelé
Disponible en ligne et une fois par mois par email. Vocabulaire Electrotechnique International (IEV) en ligne.
Service Clients - webstore.iec.ch/csc
Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-
nous: sales@iec.ch.
CONTENTS
FOREWORD . 2
INTRODUCTION . 4
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and abbreviated terms . 5
3.1 Terms and definitions. 5
3.2 Abbreviated terms . 5
4 Overview . 5
5 QoE parameters . 6
5.1 General . 6
5.2 Video quality . 7
5.3 Audio quality . 8
5.4 Synchronization . 8
5.5 Accessibility . 9
5.6 Interoperability . 9
5.7 Participation . 10
5.8 Openness . 10
5.9 UI and UX . 10
6 Requirements for QoE functional operations . 11
6.1 General . 11
6.2 QoE initialization . 12
6.3 QoE monitoring . 12
6.4 QoE evaluation . 13
7 Requirements for QoE functional entities . 13
7.1 General . 13
7.2 Multimedia conferencing server (MCS) . 14
7.3 Multimedia conferencing client (MCC) . 14
7.4 QoE measurement agent (QMA) . 14
7.5 QoE measurement manager (QMM) . 14
Bibliography . 15
Figure 1 – Functional entities and operations for QoE measurement . 11
Table 1 – List of parameters for QoE measurement . 7
Table 2 – Requirements for QoE functional entities . 13
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
User’s quality of experience on multimedia conferencing services -
Part 2: Requirements
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 63478-2 has been prepared by IEC technical committee TC 100: Audio, video and
multimedia systems and equipment. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
100/4246/CDV 100/4339/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 63478 series, published under the general title User’s quality of
experience on multimedia conferencing services, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
INTRODUCTION
With the global COVID-19 pandemic, meetings for business and education purposes shifted
from face-to-face to virtual. Consequently, a range of multimedia conferencing services were
developed, enabling users to choose and enjoy conferencing services based on personal
preferences. To ensure optimal user experience, it is essential to measure the quality of
experience (QoE) for multimedia conferencing services. However, there is currently a lack of
standardized methods for measuring a user's QoE in this context. Thus, there is a pressing
need to provide standards for measuring and evaluating a user's QoE for multimedia
conferencing services.
Traditionally, quality of service (QoS) has been measured for network data communication,
represented by objective index values like delay, throughput, and jitter. In contrast, QoE
represents a user's level of satisfaction with a specific service and reflects a human emotional
quality. As such, QoE is subject to overall service performance from the user's perspective. In
the case of multimedia conferencing services, measuring QoE is challenging due to varying
user preferences, as well as varying services and application characteristics. Therefore, a
unified framework is necessary to measure and evaluate a user's QoE for multimedia
conferencing services.
This document aims to provide standards for enhancing a user's QoE for multimedia
conferencing services. The IEC 63478 series specifies general considerations and
requirements to enhance a user's QoE and measurement methods for associated QoE
parameters.
The IEC 63478 series consists of the following parts:
– Part 1: General;
– Part 2: Requirements; and
– Part 3: Measurement methods .
IEC 63478-1 (Technical Report) describes general considerations to measure users’ QoE.
IEC 63478-2 (International Standard) describes the requirements to be considered to measure
users’ QoE.
IEC 63478-3 (International Standard) describes the measurement methods for QoE
parameters.
___________
Under preparation. Stage at time of publication: IEC CDV 63478-3:2025.
Under preparation. Stage at time of publication: IEC CDV 63478-3:2025.
1 Scope
This part of IEC 63478 describes the requirements to measure users’ quality of experience
(QoE) on multimedia conferencing services.
2 Normative references
There are no normative references in this document.
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
3.2 Abbreviated terms
Abbreviated term Full term
API/SDK Application programming interface / Software development kit
MCC Multimedia conferencing client
MCS Multimedia conferencing server
QMA QoE measurement agent
QMM QoE measurement manager
QoE Quality of experience
UI User interface
UX User experience
4 Overview
One crucial aspect of multimedia conferencing services is the quality of experience (QoE),
which describes a user's overall satisfaction level with a particular service. It measures how
well a service meets users' expectations and needs and can be influenced by various factors
including audio and video quality, responsiveness, reliability and ease of use. As the use of
multimedia conferencing services for remote communication increases, the importance of
measuring user QoE also increases. Reliable and high-quality services that meet user
expectations are essential for continued use and to prevent users from switching to other
providers. Therefore, a QoE measurement standard for multimedia conferencing services is
required to ensure a consistent and high-quality user experience across various platforms,
services and devices.
Moreover, QoE measurement standards can help service providers optimize their services and
identify areas for improvement. By measuring and analyzing QoE, service providers can identify
service problems and take corrective action to improve service quality. QoE measurement
standards allow service providers to compare services with other providers and benchmark
service quality. The complex nature of multimedia communications underscores the need for
QoE measurement standards in multimedia conferencing services. Quality issues such as
latency, jitter, packet loss and network congestion can affect the user experience and degrade
QoE, making it essential to measure and optimize QoE to provide a high-quality user experience.
The key factors for effective QoE measurement include the QoE parameters to be measured
and the QoE measurement operations to be performed among the QoE functional entities.
These QoE parameters are subdivided into QoE factors, which are classified into 'mandatory'
and 'optional' depending on their impact on QoE. The QoE measurement in multimedia
conferencing services can be measured by measuring the QoE factor, which is measured
through the operation between functional entities. To measure QoE, the following operations
are required.
a) QoE initialization: This is a procedure for parameter negotiation and measurement method
negotiation between QoE functional entities when a multimedia service begins.
b) QoE monitoring: This is the process of measuring parameters and aggregating the
measured QoE parameter values to measure the QoE of multimedia services.
c) QoE evaluation: This is the process of analysis of the aggregated QoE parameters by QMM
and report of QoE measurement results to MCS.
The QoE in multimedia conferencing services shall be measured through these requirements
for QoE measurement.
5 QoE parameters
5.1 General
To measure users’ QoE for multimedia conferencing services, it is necessary to consider a
variety of QoE parameters, which can consist of video quality, audio quality, video and audio
synchronization, accessibility, interconnectivity, openness, participation and UI/UX as
described in Table 1. Each QoE parameter can be measured with a set of QoE factors. Some
QoE factors shall be used as mandatory for effective QoE measurement, whereas the others
may be employed optionally. For measurement of a specific QoE factor, subjective and/or
objective approaches can be used. Subjective measurement is based on user feedback,
whereas objective measurement is based on the quantitative measurement of multimedia
conferencing services. The detailed method of QoE parameters shall be negotiated among the
concerned QoE functional entities.
Table 1 – List of parameters for QoE measurement
QoE parameter QoE factor Mandatory/optional
Visual clarity Mandatory
Video quality
Latency Mandatory
Clarity Mandatory
Noise Mandatory
Audio quality Latency Mandatory
Dynamic range Optional
Echo cancellation Optional
Accuracy Mandatory
Synchronization Adaptive Optional
Consistency Optional
Support for assistive technologies Mandatory
Accessibility Compatibility with assistive devices Optional
Captioning and transcription Mandatory
Cross-platform compatibility Mandatory
Interoperability Integration with other services Mandatory
Security Mandatory
User group size Mandatory
Participation
Collaboration tools Mandatory
Transparency Optional
Openness
Open API/SDK Optional
Intuitive and user-friendly design Mandatory
Consistency across platforms Optional
UI and UX
Customizability Optional
Feedback and notifications Mandatory
5.2 Video quality
Video quality is a critical factor in measuring QoE in multimedia conferencing services, as it
determines the perceived visual clarity and smoothness of the video stream during multimedia
conferencing services. Video quality is affected by several factors such as network bandwidth
and latency. Service providers can also provide settings and tools for users to adjust the video
quality to suit their specific needs and preferences.
To measure the video quality of multimedia conferencing services, the required QoE parameters
include the following:
– Visual clarity
Service providers should ensure that their services deliver high visual clarity to ensure that
users can clearly see other participants and their visual aids during meetings.
– Latency
Latency is the time delay between when video data is captured and when it is displayed on
the screen. High latency can cause problems such as stuttering and freezes in the video,
which can affect QoE level.
General methods for assessing audio and video communication systems are described in
IEC 62251, which can serve as an informative reference for evaluating multimedia conferencing
services. Subjective video quality assessment methods, as specified in
ITU-T Recommendation P.910, are also relevant references for evaluating user-perceived
video quality.
5.3 Audio quality
High-quality audio is critical to ensuring effective communication in multimedia conferencing
services. Therefore, service providers should prioritize audio quality to ensure a high level of
QoE by ensuring that their services provide sufficient bandwidth and network reliability to
support high-quality audio streams.
The audio quality of the multimedia conferencing services can be measured with the following
QoE parameters:
– Clarity
The clarity of audio is a critical aspect in determining audio quality as it enables participants
to hear each other clearly and comprehend the discussion. The absence of distortion, echo,
or background noise significantly enhances the user experience.
– Noise
In multimedia conferencing services, high levels of background noise can significantly
reduce the intelligibility of the audio and affect the user experience.
– Latency
Latency refers to the delay between the time when audio is captured and when it is played
back. Excessive latency can lead to synchronization issues and delays in the transmission
of participants’ speech and video, ultimately compromising the user experience.
– Dynamic range
Dynamic range refers to the contrast between the softest and loudest sounds in a given
piece of audio. A high dynamic range can enhance the user experience by providing clear
and distinct audio, with each sound and voice being easily distinguishable and
understandable.
– Echo cancellation
Echo cancellation allows a system to effectively eliminate echoes from audio. Reverberation
caused by audio feedback or room reflections can be highly distracting and significantly
reduce overall audio quality.
General methods for assessing audio and video communication systems are described in
IEC 62251, which can serve as an informative reference for evaluating multimedia conferencing
services. Subjective video quality assessment methods, as specified in
ITU-T Recommendation P.910, are also relevant references for evaluating user-perceived
video quality.
5.4 Synchronization
Synchronization is a crucial aspect of multimedia conferencing services, as it ensures that audio
and video streams are aligned and delivered in a synchronized manner. In multimedia
conferencing, the audio and video streams should be closely synchronized to prevent confusion
and frustration among participants.
The synchronization can be measured with the following QoE parameters:
– Accuracy
Accurate synchronization is crucial for ensuring that the audio and video streams are
precisely aligned without any noticeable differences in sight or sound. Any synchronization
errors can lead to lip-sync issues or other anomalies that can have a negative impact on the
user's experience.
– Adaptive
The adaptive parameter allows for the dynamic modification of synchronization parameters
according to network conditions and other factors. In case of network fluctuations, it is
possible that it will be necessary for the synchronization algorithms to adjust the delays or
buffer sizes to ensure the proper synchronization of the audio and video streams.
– Consistency
The consistency parameter allows for the maintenance of stable and reliable
synchronization over time, as fluctuations or errors in synchronization can negatively impact
the user experience and lower the overall QoE.
Measurement methods for synchronization of audio and video equipment and systems are
described in IEC 62312-1-1, which may serve as an informative reference. Guidelines for
synchronization methods of audio and video systems are given in IEC 62312-2, which can be
considered as additional background for synchronization considerations.
5.5 Accessibility
Accessibility refers to the degree to which participants can access and participate in the
conference call, regardless of any physical or technological limitations they might have. To
ensure the utmost level of accessibility, multimedia conferencing services should be designed
with the diverse needs of all users in mind. This includes providing various tools and functions
to accommodate users with visual or hearing impairments, such as closed captioning, audio
descriptions, or sign language interpretation.
The accessibility in multimedia conferencing services can be measured with the following QoE
parameters:
– Support for assistive technologies
Multimedia conferencing services should support various assistive technologies such as
screen readers, speech recognition software, and keyboard navigation. This makes it easier
for users with disabilities to access and use the service.
– Compatibility with assistive devices
Multimedia conferencing services should be compatible with various assistive devices such
as hearing aids, screen magnifiers, and speech recognition software. This allows users with
disabilities to access the service using their preferred assistive devices.
– Captioning and transcription
Multimedia conferencing services should support captioning and transcription to enable
users with hearing impairments or those who prefer to read captions to access meeting
content.
5.6 Interoperability
Interoperability serves as a measure of compatibility with other services, reflecting the ability
of a multimedia conferencing service to deliver a high-quality user experience while offering a
flexible and diverse service environment that plugs within other services.
To measure the interoperability, the following QoE parameters are required:
– Cross-platform compatibility
To ensure users can join meetings seamlessly, a multimedia conferencing service should
® ® ®
be compatible with a wide range of platforms, including Windows , macOS , iOS , and
®3
Android .
___________
3 ® ® ® ®
Windows , macOS and iOS and Android are examples of suitable products available commercially. This
information is given for the convenience of users of this document and does not constitute an endorsement by
IEC of these products.
– Integration with other services
Seamless integration with email, calendar, and collaboration tools is crucial for multimedia
conferencing services to enable easy scheduling and communication.
– Security
Interoperability necessitates incorporating security features such as authentication and
encryption to safeguard user privacy and prevent unauthorized access to conferences.
5.7 Participation
Engagement is the ability of users to actively participate and collaborate with others using
multimedia conferencing services. To ensure a high level of participation, these services should
provide a variety of features and tools. This includes the hand-raising ability for users, content
sharing options, and real-time collaboration tools such as whiteboards and chat rooms.
To measure the participation of users, the following QoE parameters are required:
– User group size
In multimedia conferencing services, the QoE requirement of user group size represents the
maximum number of participants that a conference can support while maintaining a high
level of quality of service. It is important to strike a balance between supporting a large
number of participants at once and maintaining quality of service.
– Collaboration tools
Multimedia conferencing services should offer user-friendly collaboration tools such as
screen sharing, virtual whiteboards, and annotation tools to facilitate active participation
and collaboration among users.
Interactive test methods for audiovisual communications, as described in
ITU-T Recommendation P.920, may serve as an informative reference for evaluating real-time
interaction and participation in multimedia conferencing services.
5.8 Openness
To facilitate seamless content sharing and collaboration, multimedia conferencing services
should be open to integration with other applications and services. This means that service
providers should prioritize openness in their design and development efforts, and provide open
APIs and SDKs that allow third-party developers to create custom integrations and extensions.
By doing so, users can share content and collaborate in a flexible and efficient way across
multiple platforms and services.
The level of openness can be measured with the following QoE parameters:
– Transparency
To ensure user trust and privacy, multimedia conferencing services should be transparent
about their policies, terms of service, and data privacy practices.
– Open API/SDK
The service providers should provide open APIs and SDKs that allow third-party developers
to create custom integrations and extensions.
5.9 UI and UX
The UI and UX of a service are crucial for its design, functionality, and overall user experience.
A well-designed UI and UX facilitates easy and efficient navigation of the service, reducing user
frustration and enhancing the overall experience. This can be achieved by providing clear and
intuitive controls for audio and video settings, enabling seamless content sharing and
collaboration, and offering a variety of customization options that cater to the diverse needs of
different users.
The UI and UX can be measured with the following QoE parameters:
– Intuitive and user-friendly design
A multimedia conferencing service should have an intuitive and user-friendly design that
allows users to easily navigate and use the service. This includes providing clear and
concise instructions, simple-to-use controls, and a logical layout, ensuring a seamless user
experience.
– Consistency across platforms
Multimedia conferencing services should ensure a consistent UI and UX across multiple
platforms, including desktop, mobile, and web-based applications. This enables users to
seamlessly switch between platforms without the need to learn a new interface, resulting in
a smoother and more convenient experience.
– Customizability
Multimedia conferencing services can enhance user experience by allowing them to
personalize their UI and UX based on their specific needs and preferences. This includes
providing options to customize the color scheme, font size, layout, and other elements of
the interface.
– Feedback and notifications
Clear feedback and notifications are essential for multimedia conferencing services to keep
users informed of important events, such as when participants join or leave a conference.
Providing such feedback ensures that users are aware of ongoing activities, and helps them
to effectively track and manage meetings.
6 Requirements for QoE functional operations
6.1 General
Figure 1 shows the functional entities for QoE measurement and management, as also given in
IEC 63478-1, which include multimedia conferencing client (MCC), multimedia conferencing
server (MCS), QoE measurement agent (QMA), and QoE measurement manager (QMM).
Figure 1 – Functional entities and operations for QoE measurement
As described in Figure 1, when a multimedia conferencing service is initialized (step 1), the
operations for measuring users’ QoE shall also be initialized. These QoE operations can be
categorized into the three functions: initialization, monitoring, and evaluation. The initialization
function can be further divided into the QoE measurement initialization (step 2) and the QoE
parameter initialization (step 3). The monitoring function can be further divided into the QoE
parameter measurement (step 4) and the aggregation of measured QoE parameter values
(step 5). The evaluation function can be further divided into the analysis for the aggregated
QoE parameters by QMM and the report of the analysis results to the server (step 6).
For effective QoE measurement, the following functions shall be provided:
– QoE initialization with the parameter negotiation and the measurement method negotiation
among QoE functional entities;
– QoE monitoring with the measurement of the QoE parameter and the aggregation of
measured QoE parameter values; and
– QoE evaluation with the analysis for the aggregated QoE parameters and the report of the
analysis results to the server.
6.2 QoE initialization
Before multimedia conferencing services begin, the information required for QoE measurement
shall be initialized and negotiated among the QoE functional entities. The QoE initialization
function is divided into the parameter negotiation and the measurement method negotiation
among QoE functional entities as follows:
– Parameter negotiation
The list of QoE parameters to be measured in the multimedia conference session shall be
determined, which will be done by negotiation or interaction between QMM or QMA and
MCS or MCC. For example, QMM and QMA can suggest a candidate list of QoE parameters
to MCS and MCC. Based on the suggested candidate list, MCS or MCC will choose the QoE
parameters to be measured appropriately by considering its environment factors, such as
device type and user group size. The list of QoE parameters to be measured shall be
informed to QMA and further to QMM.
– Feedback and notifications
The specific QoE measurement method shall be determined, which includes how to measure
QoE parameters by MCC and MCS and how to report the measured QoE parameter values
to QMA and QMM. For example, MCC or MCS can measure the QoE parameter values by
using its application or feedback from human users. MCC and MCS can deliver the
measured QoE parameter values to QMA and QMM periodically or when a specific event
occurs. Such information associated with QoE measurement method shall be negotiated
and determined in the initialization process. In addition, if there are many QMAs in the
service, a specific QMA shall be designated for each MCC for the measurement process.
6.3 QoE monitoring
For effective QoE monitoring of multimedia conferencing services, it is necessary to measure
the QoE parameters at MCS and many MCCs by applications or user feedback. The measured
QoE parameter values shall also be delivered to QMA and aggregated by QMM in a timely
manner for QoE evaluation.
The QoE monitoring function is further divided into the QoE parameter measurement operation
and the aggregation of measured QoE parameter values.
– Parameter measurement
For a multimedia conferencing service, MCC or MCS will be able to measure a variety of
QoE parameters by using its multimedia conferencing service or feedback of user, as per
the negotiation that was carried out in the initialization phase. When a large number of MCC
clients participate in multimedia conferencing services, a specific group of clients can
perform the QoE parameter measurement operation. In this case, the concerned condition
shall be negotiated in the initialization process.
– Aggregation of measured QoE parameter values
The MCC or MCS shall report its measured QoE parameter values to QMA periodically or
when requested to do so by the QMA. Each QMA shall aggregate the measured QoE
parameter values, and then send the aggregated QoE parameter values to QMM.
6.4 QoE evaluation
The aggregated QoE parameter values shall be evaluated to obtain insights or to derive some
actions for QoE enhancement, such as guiding MCS on how to improve users’ QoE or to use
the resources efficiently. The QoE evaluation function is further divided into the analysis for the
aggregated QoE parameters by QMM and the report of the analysis results to MCS.
– Analysis of the aggregated QoE parameters by QMM
QMM shall analyse and diagnose the overall QoE for multimedia conferencing services,
based on the aggregated information of measured QoE parameter values. A variety of
techniques, such as artificial intelligence, can be used for effective QoE analysis.
– Report of QoE measurement result to MCS
The QMM can report the analysed results of QoE measurement to MCS, which will be helpful
for MCS to prepare some actions for enhancement of users’ QoE.
7 Requirements for QoE functional entities
7.1 General
The QoE measurement comprises the three functions: initialization, monitoring, and evaluation.
Each function can be divided into the two specific functional operations. Table 2 summarizes
the functional operations that shall be performed by each QoE functional entity.
Table 2 – Requirements for QoE functional entities
Function Operation QMM QMA MCS MCC
Parameter negotiation Yes Yes Yes Yes
QoE initialization
Measurement method negotiation Yes Yes Yes Yes
Parameter measurement No No Yes Yes
QoE monitoring
Aggregation of measured QoE Yes Yes Yes Yes
Analysis of aggregated QoE Yes No No No
QoE Evaluation
Report of QoE measurement Yes No Yes No
7.2 Multimedia conferencing server (MCS)
MCS represents a server entity managed by a multimedia conferencing service provider, and it
shall perform the following functional operations:
– QoE parameter initialization and negotiation with QMA and QMM;
– QoE measurement method initialization and negotiation with QMA and QMM;
– measurement of QoE parameter values based on the negotiation with QMA and QMM;
– delivery of the measured QoE parameter values to QMA; and
– processing of QoE measurement results from QMM.
7.3 Multimedia conferencing client (MCC)
MCC represents the client entity that participates in the multimedia conference session, and it
shall perform the following functional operations:
– QoE parameter initialization and negotiation with QMA and QMM;
– QoE measurement method initialization and negotiation with QMA and QMM;
– delivery of the measured QoE parameter values to QMA; and
– measurement of QoE parameter values based on the negotiation between QMA and QMM.
7.4 QoE measurement agent (QMA)
The QMA acts as an arbitrator between the QMM and the MCS and/or the MCC during the QoE
measurement, and it shall perform the following functional operations:
– QoE parameter initialization and negotiation with MCS;
– QoE measurement method initialization and negotiation with MCS; and
– aggregation of measured QoE parameter values from MCS.
7.5 QoE measurement manager (QMM)
The QMM is responsible for overall management of QoE measurement, and it shall perform the
following functional operations:
– QoE parameter initialization and negotiation with MCS and MCC via the QMA;
– QoE measurement method initialization and negotiation with MCS and MCC via the QMA;
– aggregation of measured QoE parameter values from the QMA;
– analysis of aggregated QoE parameters; and
– report of the QoE measurement results to MCS.
Bibliography
IEC 62251, Multimedia systems and equipment - Quality assessment - Audio-video
communication systems
IEC 62312-1-1, Guideline for synchronization of audio and video - Part 1-1: Measurement
methods for synchronization of audio and video equipment and systems - General
IEC 62312-2, Guideline for synchronization of audio and video - Part 2: Methods for
synchronization of audio and video systems
IEC TR 63478-1:2023, User’s quality of experience on multimedia conferencing services -
Part 1: General
Recommendation of ITU-T P.910, Subjective video quality assessment methods for multimedia
applications
Recommendation of ITU-T P.911, Subjective audiovisual quality assessment methods for
multimedia applications
Recommendation of ITU-T P.920, Interactive test methods for audiovisual communications
___________
SOMMAIRE
AVANT-PROPOS . 2
INTRODUCTION . 4
1 Domaine d'application . 5
2 Références normatives . 5
3 Termes, définitions et termes abrégés . 5
3.1 Termes et définitions .
...












Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.
Loading comments...