> Whilst there are still many addresses unallocated the available space has been sharply decreased. The discovery of intelligent life on other solar systems with the parallel discovery of a faster-than-light transport stack is the main cause. This enables real time communication with them, and has made the allocation of world-size address spaces necessary, at the level 3 routing hierarchy. There is still only 1 global (spatial) level 2 galaxy wide network required for this galaxy, although the establishment of permanent space stations in deep space may start to exhaust this. This allows level 1 to be used for inter-galaxy routing. The most pressing problem now is the case of parallel universes. Of course there is the danger of assuming that there is no higher extrapolation than parallel universes...
RFC 1606 - A Historical Perspective On The Usage Of IP Version 9
https://tools.ietf.org/html/rfc1606
> Whilst there are still many addresses unallocated the available space has been sharply decreased. The discovery of intelligent life on other solar systems with the parallel discovery of a faster-than-light transport stack is the main cause. This enables real time communication with them, and has made the allocation of world-size address spaces necessary, at the level 3 routing hierarchy. There is still only 1 global (spatial) level 2 galaxy wide network required for this galaxy, although the establishment of permanent space stations in deep space may start to exhaust this. This allows level 1 to be used for inter-galaxy routing. The most pressing problem now is the case of parallel universes. Of course there is the danger of assuming that there is no higher extrapolation than parallel universes...