Enhanced Cluster-based CoAP in Internet-of-Things Networks

Recently, the Constrained Application Protocol (CoAP) has been developed for remote control of sensor devices in Internet of Things (IoT) networks. In CoAP, since the sensor and the server communicate with each other on a one-to-one basis, the load on the server will increase as the number of sensors increases. To overcome this limitation of CoAP, there is a simple extension of the CoAP using a clustering approach: cluster-based CoAP for message queueing. In this paper, we propose an enhanced cluster-based CoAP scheme for efficient gathering of sensing data. By using a cache memory on the cluster head, the communication performance can be improved in the IoT networks. From testbed experimentation of the enhanced cluster-based CoAP, we can see that the proposed scheme provides better performance than the CoAP and existing cluster-based CoAP scheme, in terms of bandwidth utilization. In addition, the load given to sensor can be alleviated with the help of the proposed scheme.