From ‘Quality-of-Service’ and ‘Quality-of-Design’ to ‘Quality-of-Experience’: A holistic view on future interactive telecommunication services

Telecommunications research can no longer be considered to be pure communications engineering. The convergence of fixed-line and mobile telephony with the Internet together with the rise of novel technologies for rapid service creation has made economic efficiency and user acceptance/usability to crucial factors for the success of the telecommunication business as such. In the emerging new paradigm, a holistic view onto the entire value chain from basic architectural concepts over the efficient design and implementation of new services and applications up to the end customer is becoming indispensable. Within this broad interdisciplinary field, the present paper focuses on the evolution of corresponding concepts for service quality. Whereas the traditional notion of \´QoS\´ (Quality-of-Service) is already well-established and has led to a plethora of research work mainly in the area of network architectures and protocols, the quality of service design (\´QoD\´) has by far not received comparable attention in the research community. Nevertheless, we argue that both concepts are equally important for achieving a sufficient quality of user experience (\´QoE\´) which eventually leads to both economic viability and user satisfaction. To illustrate our claim, we discuss recent developments in the area of QoS-enabled next generation network architectures as well as novel user-centric service design paradigms, examples for the resulting QoE evaluations and a novel HCI lab approach which allows flexible user tests of mobile applications "in the wild".