In “The City & the City“, China Miéville imagines an usual coexistence arrangement between two cities located in the same geographical area that provides a surprisingly apt metaphor for the concept of network slicing in 5G networks — from the city & the city to the network & the network.
The two cities: Besźel and Ul Qoma occupy the same physical location, with buildings, squares, streets and parks either allocated completely to one city or “crosshatched”, that is, shared. The separation and isolation between the two cities is not ensured by physical borders, but is rather enforced by cultural customs and legal norms. The inhabitants of each city are taught from childhood to “unsee” anything that lies in the other city, consciously ignoring people, cars and buildings, even though they share the same sidewalks, roads and city blocks. Recognition of “alter” areas and citizens is made possible by the different architectures, language and clothing styles adopted in the two cities. Breaching the logical divide between Besźel and Ul Qoma by entering areas or interacting with denizens of the other city is a serious crime dealt with by a special police force. (Prospective tourists in Besźel or Ul Qoma are required to attend a long preliminary course to learn how to “unsee”.)
And now for the two networks: Experts predict an upcoming upheaval in telecommunication networks to parallel the recent revolution in computing brought on by cloudification. Just as computing and storage have become readily available on demand to individuals, companies and governments on shared cloud platforms, network slicing technologies are expected to enable the on-demand instantiation of wireless services on a common network substrate. Networking and wireless access for, say, a start-up offering IoT or vehicular communication applications, could be quickly set up on the hardware and spectrum managed by an infrastructure provider. Each service would run its own network on the same physical infrastructure but on logically separated slices — the packets and signals of one slice “unseeing” those of the other. In keeping with the metaphor, ensuring the isolation and security of the coexisting slices is among the key challenges facing this potentially revolutionary technology.