The NICT operates JGN-X, an ultra-high speed wide-area network testbed for research and development. In Feb. 2016, NICT conducted an experiment in collaboration with industry, government and academia, and succeeded in transmitting encrypted 8K UHD (7,680'4,320 pixels, 16x the resolution of HDTV) uncompressed video streaming. The key points of this experiment are: 1. Encrypted 8K uncompressed video stream transmission We succeeded in 8K uncompressed video stream (approx. 24Gbps) transmission with real-time IPsec encryption that can protect the data against network sniffing and falsification from attackers. We tried with several different IPsec implementations to encrypt real-time video streaming and achieved secure streaming using AES with a 128-bit and 256-bit key. This success will be a milestone for the realization of secure 8K UHD broadcasting services. 2. 8K uncompressed video multicast throughout Japan Last year, we had build a network system for 8K uncompressed IP multicast streaming over JGN-X and this was the first over-10Gbps-multicast experiment in the wide-area network. This year, we achieved 8K uncompressed multicast video stream throughout Japan over JGN-X and SINET5. We also performed 4K video transmission to/from Bangkok, Thailand. 3. Experimental network management system with SDN The experimental system includes a lot of video devices as well as network devices which are operated by different team members. One of the main difficulty in the experiment is to switch over several IPsec implementations in short time without changing a lot of video devices geographically separated. We build an experimental network management system by adding SDN switches between video devices and network devices to change the packet destination. This enables operators to remotely change configurations at a time and to reduce operational overhead.