Decentralized Stream Processing Over Web-Enabled Devices

Thanks to the recent introduction of peer-to-peer communication between browsers with WebRTC, real time processing of streams can now be deployed on browsers in addition to traditional server-side execution environments. In this paper we present the Web Liquid Streams framework for building and executing stream processing topologies capable of gathering data from Web-enabled sensors and process it through JavaScript operators scattered across a peer-to-peer Cloud of computing peers. i) support for arbitrary topologies and data streams, ii) deployment on heterogeneous Web-enabled devices, iii) transparent stream delivery across the WebRTC, WebSockets and ZeroMQ protocols, iv) stateful and stateless operators. WLS takes care of the deployment of the topology on the available resources, while users are only required to implement the operators and describe the topology graph using JSON. The structure of the topology can be dynamically adapted without stopping the stream flowing through it. We present the platform and its programming interface, showing a first evaluation of the system.