In order to provide various attractive services to users, a user-centric approach such as usergenerated contents and services and a platform which can create a service easily and efficiently have been studied and designed during the past two decades. The IEEE NGSON standard has defined a functional architecture that provides advanced overlay functions for value-added services by collaboration of services with features of context awareness, dynamic adaptation and self-organizing management. Its service composition mechanism is comparable with service oriented architecture. However, due to SOA's complexity, it has not become as popular for user-generated services and contents as so-called mashup technologies, which also provide attractive and simple service creation. In this article we propose the adoption of loosely coupled service composition into the NGSON framework that can easily integrate existing communications and data services with little to no dependence on the underlying implementation and service description language details. Furthermore, the NGSON prototype supporting our proposal is presented as a proof of concept and to verify its advantages for operators, service providers, and end users.