The goal of this research is to provide the mobile network installed in trains faster than 300 km/h with faster than 1 Gbps IPv6 connectivity and to achieve fast handover. For faster than 1 Gbps connectivity, infrared communication devices are employed. As the network mobility protocol in IPv6, NEMO Basic Support Protocol is adopted. This paper focuses on a fast handover mechanism in the network layer. For fast handover, a cross-layer architecture called CEAL is employed. The proposed fast handover mechanism was installed on Linux. As the first step of the goal, we had a field test using a train in service of JR-West (West Japan Railway Company). The speed of the train is 120 - 130 km/h. The total handover time is 124.0 msec in the best case. Bi-directional video streaming was also succeeded.