Increasingly many work processes depend on Information and Communication Technology (ICT) services. These define the efficiency of how tasks are solved. The perceived usability of a service is heavily linked to the performance of the service, for instance the service responsiveness. Users do not like to wait; long response times (RTs) will interrupt their flow of thoughts and finally result in a loss of interest. Quality aspects, seen from the user’s point of view, have gained importance. While the rather traditional notion Quality of Service (QoS) is mostly related to technical quality parameters of the actual data transport, the more recently established notion of Quality of Experience (QoE) extends the notion of quality to include user perception and expectations. Obviously, QoE has strong subjective components and is also connected to the situation and context in which the user finds him- or herself. This work aims at finding quantitative relationships between QoE and QoS in order to provide application designers with means to adapt their application to available networks and the related conditions. We have particularly focused on a Geographical Information System (GIS) Map Service, with a web-based client-server application, used amongst others by professional users for tasks of urban planning. We have conducted user experiments to derive the relationship between user-perceived QoE, expressed qualitatively (through comments) and quantitatively (on the well-known scale from 1 = worst to 5 = best), and the response time, i.e. the time the user has to wait for the execution of a command. We have then established quantitative relationships between the response time and network problems such as losses and delays that have been generated in a controlled way using a traffic shaper between client and server.

Användarexperiment där användaren fick betygssätta en tjänst som stördes på nätverksnivå. Vi kunde bekräfta ett välkänt sammanhang mellan användarreaktion och responstider. Karttjänst, Quality of Experience (QoE), Quality of Service (QoS), responstid, MOS