The Post-IP research direction aims at defining new network architectures apt to replace the Internet architecture in twenty years. To this end, new protocols design is needed to support new applications requirements and provide autonomy as well as intelligence to a network. In this paper, we first propose a new generic protocol model designed for the Future Internet. Our proposal is based on functionality composition concept, which allows the selection and composition of functionalities on demand in order to get the required and most suitable protocol for each application, each network and each device. One of the key distinguishing features of our framework is its flexibility and self-adaptability as well as neutral-technology implementation since it provides a high infrastructure and technology transparency. To highlight the benefits of our proposed model, we present a protocol implementation based on the service oriented architecture (SOA) paradigm. In addition, we present a service-oriented reference architecture for the Nth stratum framework defined within the 4WARD consortium.