The evolution of computer networks has experienced several major steps, and research focus of each step has been kept changing and evolving, from ARPANET to OSI/RM, then HSN (high speed network) and HPN (high performance network). During the evolution, computer networks represented by Internet have made great progress and gained unprecedented success. However, with the appearance and intensification of tussle, along with the three difficult problems (service customizing, resource control and user management) of modern network, it is found that traditional Internet and its architecture no longer meet the requirements of next generation network. Therefore, it is the next generation network that current Internet must evolve to. With the mindset of achieving valuable guidance for research on next generation network, this paper firstly analyzes some dilemmas facing current Internet and its architecture, and then surveys some recent influential research work and progresses in computer networks and related areas, including new generation network architecture, network resource control technologies, network management and security, distributed computing and middleware,wireless/mobile network, new generation network services and applications, and foundational theories on network modeling.Finally, this paper concludes that within the research on next generation network, more attention should be paid to the high availability network and corresponding architecture, key theories and supporting technologies.