https://www.theregister.co.uk/2017/09/28/boffins_sling_around_entangled_photons_at_telco_wavelengths/

One of the hurdles facing photon-based quantum systems using entangled photons is that it's hard to create them at the 1550 nm wavelengths used in telecommunications systems.

Entanglements are the basis for all sorts of hot-boffin stuff: quantum information processing, repeaters, photon-based key exchange, and fully quantum communication systems.