This is an idea proposed in 2024 as a Cambridge Computer Science Part II project, and is currently being worked on by Roy Ang. It is supervised by Ryan Gibb and Anil Madhavapeddy as part of my Interspatial OS project.
Bigraphs were originally proposed as a model for the behaviour of ubiquitous systems since interaction between mobile devices is dependent on both placing (locality) and linking (connectivity). However, there has yet to be a bigraph that represents the complete physical world. Such a bigraph will enhance the computer's representation of its location from a simple latitude-longitude pair to a context more familiar to humans: the room it is in, the street the building is on, and the town the street is in. This will allow for location-aware applications and policies about connectivity of mobile devices to work based on the defined locality of buildings, streets and administrative regions.
The physical world has also long been represented by maps. OpenStreetMap
(OSM) is a freely-licensed geographic database built by a community of
volunteers through the annotation of data collected through surveys, aerial
imagery and other free geodata sources. Boasting a user base of 10 million, OSM
has labelled buildings, streets and regions with impressive detail comparable
with commercial counterparts. The map elements are supplemented with key-value
pairs called "tags" that describe characteristics of the element. Tagging
conventions vary across countries, but there are standard practices such as the
addr tag on buildings to describe its address.
This project will demonstrate modelling the physical world as a bigraph. Places marked on OSM will be hierarchically structured in a place graph, guided by administrative boundaries such as country, state, city etc. Then, a link graph will be built on top of the place graph to model the network of connected streets. The use of such bigraphs for ubiquitous systems will be demonstrated with the use case of Bluetooth connectivity, using reaction rules that allow devices to move to a new place and form links with other devices in its proximity.