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E. Fraccaroli and D. Quaglia
Subscriber
Broker
Publisher
CONNECT
CONNACK
19
PUBLISH
(Topic:"temperature/home")
19 °C
PUBACK
SUBSCRIBE
(Topic:"temperature/home")
SUBACK
19
PUBLISH
(Topic:"temperature/home")
19 °C
DISCONNECT
Fig. 3.30 Example of MQTT protocol operation at QoS Level 1
Subscriber
Broker
Publisher
CONNECT
CONNACK
19
PUBLISH
(Topic:"temperature/home")
19 °C
PUBREC
PUBREL
PUBCOMP
SUBSCRIBE
(Topic:"temperature/home")
SUBACK
19
PUBLISH
(Topic:"temperature/home")
19 °C
PUBREC
PUBREL
PUBCOMP
DISCONNECT
Fig. 3.31 Example of MQTT protocol operation at QoS Level 2