Notion of the user-centered design (UCD) is requisite to improve user satisfaction. Matching the concept of UCD, Quality of Experience (QoE) is expected to become a paradigm shift from the existing operator-initiative network services. There are, however, several difficulties to realize practical communication services based on QoE. One difficulty is how to bridge QoE and Quality of Service (QoS) parameters relevant to system performance. Moreover, since QoE is based on the end-user subjective evaluation, flexible modeling corresponding to the end-user psychological status is needed. In this paper, an interactive Web service is considered and a QoE model with end-user psychological effect is derived by use of the Weber-Fechner law. Data of QoE and QoS parameter are collected through experiments and the mapping functions between QoE and QoS are estimated from the data.

Both of Quality of Service (QoS) and Quality of Experience (QoE) are defined to specify the degree of service quality. Although they are dealt with in different layers in multi-layered models, collaboration of these is necessary to improve the user satisfaction for telecommunication services. In this paper, after sorting out the concepts and specification of QoS and QoE, a service quality coordination model combining these is proposed. The model is applied to a video-sharing service and its coordination model is derived based on subjective experiments. The structural equation modeling is used to compute the user satisfaction from QoS and QoE.

This paper presents the concept of dividing a local office service area under the present telephone network into blocks of switching areas to make up a local network with small, distributed switching nodes because switching costs will become much cheaper relative to cable laying costs due to LSI technology progress. In this paper, cable laying cost and switching cost are taken as the two main factors in determining future local network configurations. First, the cable laying cost is formulated using cable duct and circuit length. Next, the switching system cost is formulated based on the relation between capability and cost of components such as gates and memories. Finally, local telephone network cost is calculated, using the cost formulas obtained and data available at present. The conclusion is that from the cost-effective point of view, conventional local network office service areas should be divided into 9 to 16 blocks.