“…For example, how much bandwidth is exactly required for HDTV to be transferred across the network is too hard for the common user to know. Considering that the user usually cannot express such quantitative requirements for QoS parameters accurately and his judgments on things always follow the Gaussian distribution (Platenius et al, 2013), we use intervals to denote QoS parameters and use the Gaussian fuzzy membership functions (Hasan et al, 2014) to specify the bandwidth, delay, delay jitter and error rate requirement of the user desired routing service. We denote the actual bandwidth, delay, delay jitter and error rate of the route provided by the ISP as bw , de , jit and err .…”