Abstract: A network node configured to operate in an optical fiber network can comprise a quantum key distribution (QKD) communication unit adapted to communicate with another QKD communication unit of at least one other network node of the optical fiber network according to a CV-QKD mode and/or a DV-QKD mode. A control unit can be configured to control the QKD communication unit to operate in at least one of the CV-QKD mode and the DV-QKD mode. The control unit can be configured to switch operation of the QKD communication unit between the CV-QKD mode and the DV-QKD mode.

Abstract: A first environment image of a first video environment and a first video record of a subject in the first video environment may be received from a computing device in a fixed position. Based on the first environment image and the first video record, data may be determined. The data may represent the subject separated from one or more features of the first video environment visible in the first video environment. Based on the data, a digital hologram of the subject may be caused to be represented in a second video environment.