This is the first book to introduce UUDN for 5G, including the concept, challenges, architecture and key technologies.The new network architecture based on “de-cellular” and “user-centric” is proposed with three kinds of decoupling: user plane and control plane decoupling from radio access, control and transmission decoupling from network, local service and network service decoupling.Key characteristics of UUDN are provided, including four aspects: Intelligent network knows...