A Sleep Scheme Based on MQ Broker Using Subscribe/Publish in IoT Network

Constrained Application Protocol (CoAP) is a transfer protocol that is used for Internet of Things (IoT) devices such as sensors and actuators equip with low power supply, limited computing processor, and constrained network environment. For the constrained devices of CoAP based IoT network, we present a sleepy scheme based on a Message Queue (MQ) broker that supports the subscribe/publish communication architecture in the IoT middleware to enable the devices having better energy consumption. The IoT middleware is a server that providing services for storing and retrieving information of IoT node using Resource Directory (RD) functionality, and supporting the sleepy scheme using MQ broker functionality. The RD provides HTTP services to the HTTP client based application for discovering and looking up information of IoT nodes which are registered to the RD. The functionality of MQ broker is used for performs store-and-forward messaging. The MQ provides the service for IoT nodes to publish data to the middleware. The data shall be subscribed by the client application. The IoT node in the sleep mode that cannot be accessed by the client. Through the IoT middleware, the client can subscribe the IoT node for getting the result from IoT node after wake up. Once the IoT node wakes-up from the sleep status, the IoT middleware publishes the subscribed result to the client.