TY - JOUR T1 - Rate Control Scheme for Improving Quality of Experience in the CoAP-based Streaming Environment AU - Kang, Hyunsoo AU - Park, Jiwoo AU - Chung, Kwangsue JO - Journal of KIISE, JOK PY - 2017 DA - 2017/1/14 DO - 10.5626/JOK.2017.44.12.1296 KW - internet of things KW - streaming KW - quality of experience AB - Recently, as the number of Internet of Things users has increased, IETF (Internet Engineering Task Force) has released the CoAP (Constrained Application Protocol). So Internet of Things have been researched actively. However, existing studies are difficult to adapt to streaming service due to low transmission rate that result from buffer underflow. In other words, one block is transmitted one block to client’s one request according to the internet environment of limited resources. The proposed scheme adaptively adjusts the rate of CON(Confirmable) message among all messages for predicting the exact network condition. Based on this, the number of blocks is determined by using buffer occupancy rate and content download rate. Therefore it improves the quality of user experience by mitigating playback interruption. Experimental results show that the proposed scheme solves the buffer underflow problem in Internet of Things streaming environment by controlling transmission rate according to the network condition.