 showing the level of quality that customer/user (QoSE) customers/users believe they have experienced with the service usage. Criterion Collections of appropriate characteristics used to describe benefit to user of the service. Parameter A quantifiable characteristic of a service with given scope and specified boundaries (minimum or maximum). Objective (quantitative) parameters Parameters measurable with instruments or observations. Subjective (qualitative) parameters Parameters expressed by using human judgment. Measure A unit by which a parameter can be expressed at measurement. Metric (i.e. "indicator") Value which is calculated from observed attributes of a measure. Service A set of functions offered to a user by a service provider. A person or entity external to the telecommunication network, which uses connections through the network for communication. Customer A user who is responsible for payment for the services based on agreement with the service provider (e.g. telecom operator). Network performance The ability of a network or its portion to provide the technical functions related to communications between users. Network provider An organization/company which owns a telecommunications network for the purpose of transporting bearers of telecommunication services. Service provider An organization/company which provides telecommunication services to users and customers. Internet (including video as the most demanding service regarding bitrates, i.e. band- width) was starting to happen with the development of broadband access to the IP-based networks and provision of IP-based services (via such broadband access). The convergence onto the Internet as a single networking platform for all services is possible only with development of broadband access to the Internet, including fixed access and mobile access networks. Although broadband is a relative terminology with References respect to the bitrates which provide seamless access to all existing applications and ser- vices at the present time, the term ultra-b