These were first highlighted by the Awakened faction who paid freelancers to investigate.
A small transmitter device was located and hacked into. It was sending information to a second point on a very tightly focused beam. Analysis suggests the transmitted contained nanotechnology manufacturing instructions of some kind. The hack was swiftly discovered and destroyed, and the hacker was attacked in the Bar by an unknown figure that appeared out of thin air. A bounty was swiftly posted for the attacker and then claimed some time later when the attacked was shot and killed a short distance from the Bar.
These are now known to be Cortana's network of devices and they seem to be small nanite factories capable of self-repair and of manufacturing other materials from the matter around them.