Faezeh Mahmoudi - Guilan University, Iran

Next-generation network (NGN) is a new concept and become important for future telecommunication networks. This paper intends to offers a comprehensive survey of recent developments in the field of Next Generation Networks (NGN). Specifically, we focus on functional architecture as defined by the ITU-T, Management and service and transport strata of the NGN model and, within each of these, we highlight the main logic functions that have been the subject of investigation according to a service-oriented approach

Next Generation Network, Architecture of NGN, PSTN, Future Networks, Quality of Service