Laurent Lemke - Shared models and open infrastructure for the Internet of Things in smart city

Nowadays cities face several challenges and are concerned by ecological, energetical, economical, and demographical aspects. Smart cities, equipped with sensors, actuatuors, and digital infrastructures, are meant to tacle these issues.

Current smart cities are operated by several actors without sharing sensor data or accesses to the actuators. This is a vertical organization, in which each actor deploys its own sensors and actuators, and manages its own digital infrastructure. Each actor may be interested in a different aspect of city management, for instance traffic management, air control, etc.

The current trend is a transition towards a more horizontal organization, based on an open and shared mediation platform. In such a platform, sensor data and accesses to actuators can be shared among several actors. The costs related to infrastructure deployment andmanagement are therefore reduced for each individual actor.

This PhD is a contribution to this evolution towards horizontal organizations, with open and shared platforms. We propose: (1) an abstraction layer for the control and supervision of the city; (2) a concurrency management mechanism; (3) a coordination mechanism that helps sharing actuators; (4) a proof-of-concept implementation of these contributions.

The abstraction layer we propose helps users control and supervise a city. It is based upon formal models inspired by the ones used in theprogramming of reactive systems. They represent the physical elements present in each smart city, with genericity principles. In order to ease application development, the interface of those models is made uniform. Since applications, especially control ones, may have real-time constraints, we also list the constraints this poses on distributed infrastructures.

As soon as actuators are shared, conflicts may occur between users. Our proposals include a concurrency management mechanism, basedon reservation principles. We also provide a coordination mechanism for the users to be able to perform several actions in an atomic way.

All these principles have been implemented as a proof of concept.  We review several use cases, to demonstrate the potential benefits of our proposals.