ld be less than 400 ms). But with the advent of new types of com- munications where services may not require real-time delivery and where the sender or the end-user may not be a person but could be a machine (e.g. Internet of Things), it is important to keep in mind that not all services are the same, and even similar services can be treated in different ways depending on whether they are used by machines or by humans on one or both ends of a given communication session or connection. Quality of service (QoS), as defined by the ITU [10], is totality of characteristics of a telecommunications service that bear on its ability to satisfy stated and implied needs of the user of the service. Similar definitions of QoS are used by other SDOs in their standards. However, from the telecommunications/ICT point of view the QoS is always an end-to-end character- istic, which however can be split into different network segments between the ends (e.g. between two hosts on the Internet, or two telephones). However, the end-user's per- ception of a given telecommunication/ICT service is also influenced by different factors which may include (but are not limited to) social trends, advertising, tariffs, and costs, which are interrelated with the customer expectation of QoS. For example, social trends may be in terms of popular devices (e.g. smartphones), services (e.g. some services are more popular than other similar services over the Internet), applications (e.g. there is different popularity of different applications in their ecosystems), etc. Further, end-user perception of the QoS is not limited only to objective characteristics at the man-machine interface. For end-users, the QoS refers to the quality that they personally experience during their use of a given telecommunication service. The end-user may be satisfied with the QoS of a given service at a certain time and the same user may not be satisfied with the same service 10 years in the future. For example, when a user accommodates to higher resolution of TV or video st