Survey on technologies for enabling real-time communication in the web of things

Abstract

The Web of Things (WoT) can be considered as a step towards the Internet of Everything development. The concept of WoT assumes that objects of the Internet of Things (IoT) seamlessly interact with the Web by re-using web protocols wherever possible. One of the most desirable service in the WoT is real-time communication, due to the event-driven character of many IoT applications. This chapter provides an overview of the protocols which are taken into account in order to ensure real-time interaction of WoT objects. We describe two technologies: WebSocket and WebRTC, which are a part of HTML5 specification and are considered as solutions that bring real-time communication capabilities into the WoT. CoAP, a specialized protocol for use in resource constrained devices, is also presented, as well as two solutions that implement publish/subscribe interaction model. Next, we discuss which protocols can have the greatest impact on the WoT development.