Page 24 - ITU-T Focus Group Digital Financial Services – Consumer Experience and Protection

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

Due to the complexity of services and the many factors which have an influence on QoS/QoE, there is not a
close one-to-one relationship which would allow statements like "If the bandwidth is increased by 200 kbit/s,
then the rating by the user will rise by 0.5 points".
To ensure that the appropriate service quality is delivered, QoE targets should be established for each service
and be included early on in system design and engineering processes where they are translated into objective
service level performance metrics.

Quality of Experience is an important factor in the marketplace success services and is a key differentiator
with respect to competing service offerings. Subscribers to network services do not care how service quality
is achieved. What matters to them is how well a service meets their expectations (e.g. in terms of price,
effectiveness, operability, availability, and ease of use).

1.2 Services, Applications or “Popular Services”

Within the formal standardization community the term “Service” was always understood as a functionality for
which all aspects are standardized (i.e. standardized service); the concept behind was that globally all networks
would (be able and willing to) offer exactly the same – fully interoperable – harmonized service.

However, over time the terminology got corrupted in a sense that service today stands for any application. For
example the Internet Engineering Task Force (IETF) refers to their standards which basically describe network
functionalities as services.

Under end-user aspects the term service is used for any application offered in the networks; this makes it very
difficult to standardize assessment methods and target values or requirements for related KPIs.

Therefore, if we speak about services, today, we can distinguish multiple dimensions:

a) applications with global reach vs. b) locally limited applications
c) specifically named applications vs. d) application class denominators
Typical examples are:

– Netflix or YouTube™
– eGovernment application in country xyz

– Netflix or YouTube™
– Video streaming, IPTV
Since services in all these dimensions are not being standardized in their functionality a-priori, the communities
involved in assessing QoS and QoE for such services have focussed on what is called “popular services”. The
concept behind is to provide assessment methods and targets at for such services which are used frequently
by a huge number of users.

• Looking first at dimension a) with the examples given above, these are truly “popular services” – however
the underlying technical aspects, such as carrier services may be changed from time to time.

• For dimension b) the main obstacle is the limitation itself. It is highly probable that there will not any
international standard to measure the QoS or QoE of exactly one of that specific services.

• Dimension c) requires close cooperation between the stakeholder providing these services and the
standardization experts.

• Proper dealing with dimension d) requires the standardization of new end-to-end mechanisms. Otherwise
the existing carrier services will be confronted with more stringent targets for existing services.

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