However, the influence of other network
conditions such as latency and bandwidth cap were not
considered in this research. S. Bandyopadhyay et al. [11]
compared the performance of CoAP’s request-response mode
and resource-observe mode with MQTT in terms of overhead
vs. various packet sizes among two different packet loss (0%
and 20%) conditions; additionally, power consumption vs.
bytes of data communicated was also assessed in this research,
however with packet loss being considered as the only factor
characterizing the network condition. N.De Caro et al. [12]
utilized smartphones as sensing platforms, then compared the
performance of CoAP vs MQTT in terms of per-layer
bandwidth usage, round trip time (for delay), and packet
received ratio based on a 20% packet loss; this research
compared the performance difference between a TCP-based
protocol and a UDP-based protocol; however, a comparison
between two different TCP-based IoT protocols such as MQTT
and DDS was lacking.