  In this paper, we address the issue of scalable, interoperable, and timely
dissemination of information in resource-constrained IoT. Scalability is
addressed by adopting a publish-subscribe architecture. To address
interoperable and timely dissemination, we propose an HTTP/3 (H3) solution that
exploits the wide-ranging improvements made over H2. We evaluated our solution
by comparing it to a state-of-the-art work: MQTT-over-QUIC. Because QUIC and H3
have undergone standardization in tandem, we hypothesized that H3 would take
better advantage of QUIC transport than an MQTT mapping would. Performance,
network overhead, and device overhead were investigated for both protocols. Our
H3-based solution satisfied our timely dissemination requirement by offering a
key performance savings of 1 RoundTrip Time (RTT) for publish messages to
arrive at the broker. In IoT networks, with typically high RTT, this savings is
significant. On the other hand, we found that MQTT-over-QUIC put marginally
less strain over the network.
