Virtual Device Model extending NGSI-LD for FaaS at the Edge

Smart environments are composed of an ever-increasing number of heterogeneous resources and devices for collecting and processing of a large amount of context data. These activities can be performed at the edge of the smart area, over a distributed and heterogeneous infrastructure, so to be close to the end-user and optimize response time. However, it is hard to define a data model able to support data exchange among different systems and between systems and users. This paper presents the key features of a smart environment and introduces the concept of virtual device, that is an abstracted component characterized by specific high-level functionalities. Then, the paper proposes a data model useful to represent and optimize the adoption of virtual device in smart environments. To better explain the data model features and benefits, we refer to a video surveillance use case, where a smart camera is able to provide the solid angle detection as a service.