Page 22 - ITU-T Focus Group Digital Financial Services – Consumer Experience and Protection

ITU-T Focus Group Digital Financial Services
Consumer Experience and Protection

1 Introduction

This Report summarizes the Quality of Service (QoS) and Quality of Experience (QoE) aspects of Digital Financial
Services (DFS) as concluded by the Focus Group DFS.

Guidance and suggestions are provided for stakeholders involved in DFS taking into account regulatory and
consumer related aspects.

The objective is to provide guidance mainly for Telecom Regulators but also to Service Providers of DFS. One
main topic is the selection of Key Performance Indicators (KPIs) which should be focussed on.
Besides that, the report contains comments and notes which might not be appropriate for immediate guidance;
this material is considered of importance for future work.

• Annex A discusses existing standards which are related to DFS.
• Annex B introduces underlying functionalities of DFS applications.
• Annex C summarizes a possible selection of a set of KPIs appropriate for DFS

1.1 Relationship of QoS and QoE

In addition to the term QoS, the term Quality of Experience (QoE) is often used nowadays in order to stress the
purely subjective nature of quality assessments in telecommunications and its focus on the user's perspective
of the overall value of the service provided.

The increased significance of the term QoE is related to the fact that in the past the term QoS was used mostly
for only technical concepts focused on networks and networks elements. The definition of QoS, however,
does include the degree of satisfaction of a user with a service. Thus, non-technical aspects are included, like
e.g. the user's environment, his expectations, the nature of the content and its importance. But most service
providers did use the QoS only in relation to the actual user-service interaction in order to cross-check whether
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requirements have been met by the service implementation of a provider (as perceived by the user). So there
was a strong focus on the actual network performance and its immediate influence on user perceivable aspects
while additional subjective and not directly service related aspects were omitted.

QoE is defined in in Appendix I of Recommendation ITU-T P.10 as the overall acceptability of an application or
service, as perceived subjectively by the end-user. It includes the complete end-to-end system effects (client,
terminal, network, services infrastructure, etc) and may be influenced by user expectations and context. Hence
the QoE is measured subjectively by the end-user and may differ from one user to the other. However, it is
often estimated by a combination of objective measurements and metrics describing subjective elements.

NOTE: The definition of QoE and, in particular, the dividing line between QoS and QoE is, however, quite fuzzy,
and up to today it does not appear that a globally accepted definition exists. For example, the Recommendation
ITU-T E.800 does not use the term QoE at all; instead, it uses a 4-viewpoint model (similar to the one in
Recommendation ITU-T G.1000) with terminology, like QoSE (E=experienced) or QoSP (P=perceived). In any
case, the amount of energy put into the QoS/QoE discussion in the context of the FG DFS should be limited,
since this is already on the agenda of ITU-T Study Group 12 and several other organizations.

For working purposes, preferably the use of QoS can be limited to things which can be measured by machines
or technical means (including e.g. speech quality metrics, like POLQA, Rec. ITU-T P.863, which already contain
some perceptual considerations), and QoE should be used for items further down a “processing chain” where
some kind of assessment has been applied. This assessment can be, for instance, some kind of usually nonlinear
(clipping) function expressing limits where service quality is either “inacceptable” anyway, or so good that
a further improvement will not have any practical consequences. It is important to note that such limits will
be strongly dependent on previous experience, i.e. will vary between regions or countries, and will also vary

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