The Advanced Neural Activity system, or ANA, is a digital reality, consisting of both human personalities downloaded into its structure, and a multitude of virtual realities constructed by its "residents". It is the most powerful sentient "computer" ever, and has a portion of it devoted to be the government of the Commonwealth. It is not a single electronic device, rather:
ANA had ceased to be limited to the physical machinery that birthed it. The operational medium was now tunnelled into the quantum structure of spacetime around Earth ... it was no longer machine, or even artificial life. It had become alive. (The Dreaming Void)