MQTT v3.1.1 protocol has only 10 return codes. These return codes can represent little meaning, and the same return code value can have different meanings in different messages.
Compared with MQTT 3.1.1, MQTT 5.0 protocol adds many properties, which are distributed in variable headers and payloads of packet.
InfluxDB is an open source sequential database developed by InfluxData. It was written by Go and focuses on querying and storing sequential data with high performance. InfluxDB is lighter than the OpenTSDB database introduced in the previous issue, and is better than OpenTSDB in benchmarking indicators given officially by InfluxData.
NB-IoT is a new type of cellular technology developed by the 3GPP standardization organization. It belongs to the low-power wide-area (LPWA) IoT connection, that is mainly used to connect terminals with limited bandwidth resources, allowing terminals to collect and exchange data with less resources than GRPS, 3G, LTE and other technologies.
MQTT is completely different from Kafka. MQTT is a protocol and a technical standard developed by members (mostly are top engineers at IBM and Microsoft) of the OASIS Technical Committee. Kafka is an open source streaming platform that has been implemented. It was firstly developed by LinkedIn. After incubated by Apache Incubator in 2011 after opening source, it has became the top project of the Apache Software Foundation.
In our previous article we have shown how to secure EMQ connection with SSL.
Besides the benefit of multiplied service capacity, we also deploy EMQX in a cluster to achieve high availability (HA).
Erlang is a general-purpose, concurrent, functional programming language, as well as a garbage-collected runtime system.