Section: New Software and Platforms

Dioptase and Spinel: Lightweight Streaming Middleware for the IoT

Participant : Valérie Issarny [correspondent] .

Dioptase is a service-oriented middleware for developing stream-based applications which produce, process, store and consume data streams in complex environments such as the Internet of Things (IoT) and Wireless Sensor and Actuator Networks (WSAN). Dioptase leverages a novel service-oriented architecture for continuous processing, in order to deal with the large scale and the heterogeneity of the IoT. Once Dioptase is deployed onto a device, it enables developers to manage it as a generic pool of resources that can execute tasks provided over time. Those tasks are described as compositions of both standard continuous processing operators and customized computations written using a new lightweight stream processing language, called DiSPL.

The IoT infrastructure is composed of various devices (sensors, registries, proxies, clusters, etc.), and Dioptase is intended to be deployed onto all of them. To this end, Dioptase is highly modular and can be customized depending on the targeted devices and their roles in the IoT:

• Dioptase core is the base version of Dioptase that enables developers to (i) manage embedded sensors and actuators of a device through services and (ii) deploy tasks onto the device at any time.

• Dioptase task mapper is a server that implements our research on task mapping and automated deployment. Given a task graph, this server computes where to deploy each task according to the characteristics of tasks and available devices, and then manages the execution of the deployed tasks over time.

• Dioptase proxy is a pub/sub broker that enables interactions between Things that can not communicate directly, because of non-compatible networking interfaces/protocols or the use of address translation techniques.

• Dioptase exchange is a privacy proxy that manages the data and the services provided by a network of Things. It authenticates outsider Things and users, enabling them to request data streams or services according to access control and data-accuracy policies.

As part of the design of Dioptase, we have been investigating how to open legacy sensors to the future IoT. Toward this end, we propose to take advantage of the multi-modal connectivity as well as the mobility of smartphones, using them as mobile proxies that opportunistically discover close-by static sensors and act as intermediaries between them and the IoT. Spinel is a prototype of such an opportunistic proxy for mobile phones, which monitors the smartphone's mobility and further infers when to discover and register the sensors to an IoT discovery infrastructure, for instance the MobIoT registry(§  5.4 ). Spinel collects data from the close-by sensors and pushes the collected data to an IoT stream processing infrastructure, for instance the Dioptase middleware. We will shortly release both Dioptase and Spinel under open source licenses.