Gateway-Assisted Retransmission for Lightweight and Reliable IoT Communications.
Message Queuing Telemetry Transport for Sensor Networks (MQTT-SN) and Constrained Application Protocol (CoAP) are two protocols supporting publish/subscribe models for IoT devices to publish messages to interested subscribers. Retransmission mechanisms are introduced to compensate for the lack of data reliability. If the device does not receive the acknowledgement (ACK) before retransmission timeout (RTO) expires, the device will retransmit data. Setting an appropriate RTO is important because the delay may be large or retransmission may be too frequent when the RTO is inappropriate. We propose a Gateway-assisted CoAP (GaCoAP) to dynamically compute RTO for devices. Simulation models are proposed to investigate the performance of GaCoAP compared with four other methods. The experiment results show that GaCoAP is more suitable for IoT devices.
Department of Computer Science and Information Engineering, National Cheng Kung University, Tainan 701, Taiwan. momo@imslab.csie.ncku.edu.tw.
Hui-Ling
HL
Chang
Department of Computer Science and Information Engineering, National Cheng Kung University, Tainan 701, Taiwan. wjungle@gmail.com.
Cheng-Gang
CG
Wang
Department of Computer Science and Information Engineering, National Cheng Kung University, Tainan 701, Taiwan. aj211y@imslab.csie.ncku.edu.tw.
Mong-Ting
MT
Wu
Department of Computer Science and Information Engineering, National Cheng Kung University, Tainan 701, Taiwan. tsaimh@csie.ncku.edu.tw.
Meng-Hsun
MH
Tsai
Department of Computer Science and Information Engineering, National Cheng Kung University, Tainan 701, Taiwan. a711186@imslab.csie.ncku.edu.tw.
Chia-Ying
CY
Lin
Constrained Application Protocol (CoAP); Internet of Things (IoT); Message Queuing Telemetry Transport for Sensor Networks (MQTT-SN); retransmission mechanism; retransmission timeout (RTO); round-trip time (RTT)
Sensors (Basel). 2013 Jan 04;13(1):648-80
23291579