Improve IoT Streaming QoS by Determining the Message Propotion in CoAP

Recently the Internet of Things (IoT) have gain much attention and, therefore, the demands for various streaming applications based on the IoT have increased. In this regard, the Constrained Application Protocol (CoAP) is a lightweight transmission protocol widely used in the IoT environment for providing streaming services. Generally, the CoAP protocol defines two message types i.e. confirmable message and non-confirmable message. However, since CoAP is not originally a transmission protocol design for streaming applications. Therefore, it cannot guarantee the reliability and real-time performance when streaming media is transmitted over it. In this paper, we propose a method to improve the QoS of streaming media transmission by dynamically changing the proportion of confirmable messages and non-confirmable messages. As the network conditions gradually gets better, the proposed method appropriately reduces the proportion of confirmable messages to meet the real-time requirements of streaming media. Finally, the simulation results show that the proposed scheme significantly enhances the QoS of the CoAP protocol for streaming service.