In science fiction, previously often written about data transmission in space with lasers. Such a method of data transmission has long ceased to be a fiction, and soon (in the coming months) to the ISS will try to convey a certain amount of information on the Earth in this way.
Setting the data transfer is called OPALS (Optical Payload for Lasercomm Science)
In theory, the data transmission using lasers from orbit is not a problem. In practice, it may be different, since the atmosphere can be a serious hindrance to a "clean" transmission. However, experts are hoping for a successful test. If all goes well, in the future it will be possible to transmit a laser large data sets.
Now bandwidth "ISS-Earth" is 200-400 kbit / s. The laser will significantly increase the channel capacity, up to 50 Mbit / s. One of the engineers of the project compared with such update upgrade dial-up connection to DSL.
Now the equipment is still in the world, and yesterday's launch of SpaceX, which was planned to transfer the equipment to the ISS, broke. So the sooner this launch will take place, the faster hold the above data. Plan to transfer video, several rolls of 100 seconds each.