Title: Implementation and Analysis of QUIC for MQTT,
Abstract: Transport and security protocols are essential to ensure reliable and secure
communication between two parties. For IoT applications, these protocols must
be lightweight, since IoT devices are usually resource constrained.
Unfortunately, the existing transport and security protocols -- namely TCP/TLS
and UDP/DTLS -- fall short in terms of connection overhead, latency, and
connection migration when used in IoT applications. In this paper, after
studying the root causes of these shortcomings, we show how utilizing QUIC in
IoT scenarios results in a higher performance. Based on these observations, and
given the popularity of MQTT as an IoT application layer protocol, we integrate
MQTT with QUIC. By presenting the main APIs and functions developed, we explain
how connection establishment and message exchange functionalities work. We
evaluate the performance of MQTTw/QUIC versus MQTTw/TCP using wired, wireless,
and long-distance testbeds. Our results show that MQTTw/QUIC reduces connection
overhead in terms of the number of packets exchanged with the broker by up to
56%. In addition, by eliminating half-open connections, MQTTw/QUIC reduces
processor and memory usage by up to 83% and 50%, respectively. Furthermore, by
removing the head-of-line blocking problem, delivery latency is reduced by up
to 55%. We also show that the throughput drops experienced by MQTTw/QUIC when a
connection migration happens is considerably lower than that of MQTTw/TCP.