A publish subscribe based middleware for enabling real time web access on constrained device

In IoT world, web platform can be one of the promising interoperability enabler platform due to its massive success in current internet era. In order to integrate the web and IoT, a middleware with efficient communication architecture is required. In this paper, we designed and implemented publish subscribe based middleware for enabling real time web access on constrained device. The proposed system consists of three components : the sensor-actuator equipped device and its web based client counterpart acting as both publisher/subscriber, and MQTT broker. In order to send its sensing data to user, each device periodically publish a message with specific topic. In another side, user subscribe to that topic for getting the latest data from a device. The similar natures are applied for communication in reverse direction i.e. the user giving command to device. For enabling web access to the system, web based client utilize MQTT through websocket protocol to communicate with broker while the device utilize MQTT on top of pure TCP/IP stack to reduce the communication overhead. From the functional and performance testing we conclude that the proposed system is able to bridge the communication between web based client to the device with reasonable performance.